diff --git a/homeassistant/components/media_player/__init__.py b/homeassistant/components/media_player/__init__.py
index 32bf57108f7..e50b578ff1b 100644
--- a/homeassistant/components/media_player/__init__.py
+++ b/homeassistant/components/media_player/__init__.py
@@ -1,6 +1,4 @@
 """
-homeassistant.components.media_player
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Component to interface with various media players.
 
 For more details about this component, please refer to the documentation at
@@ -110,45 +108,47 @@ ATTR_TO_PROPERTY = [
 
 
 def is_on(hass, entity_id=None):
-    """ Returns true if specified media player entity_id is on.
-    Will check all media player if no entity_id specified. """
+    """Return true if specified media player entity_id is on.
+
+    Will check all media player if no entity_id specified.
+    """
     entity_ids = [entity_id] if entity_id else hass.states.entity_ids(DOMAIN)
     return any(not hass.states.is_state(entity_id, STATE_OFF)
                for entity_id in entity_ids)
 
 
 def turn_on(hass, entity_id=None):
-    """ Will turn on specified media player or all. """
+    """Will turn on specified media player or all."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_TURN_ON, data)
 
 
 def turn_off(hass, entity_id=None):
-    """ Will turn off specified media player or all. """
+    """Will turn off specified media player or all."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_TURN_OFF, data)
 
 
 def toggle(hass, entity_id=None):
-    """ Will toggle specified media player or all. """
+    """Will toggle specified media player or all."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_TOGGLE, data)
 
 
 def volume_up(hass, entity_id=None):
-    """ Send the media player the command for volume up. """
+    """Send the media player the command for volume up."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_VOLUME_UP, data)
 
 
 def volume_down(hass, entity_id=None):
-    """ Send the media player the command for volume down. """
+    """Send the media player the command for volume down."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_VOLUME_DOWN, data)
 
 
 def mute_volume(hass, mute, entity_id=None):
-    """ Send the media player the command for volume down. """
+    """Send the media player the command for volume down."""
     data = {ATTR_MEDIA_VOLUME_MUTED: mute}
 
     if entity_id:
@@ -158,7 +158,7 @@ def mute_volume(hass, mute, entity_id=None):
 
 
 def set_volume_level(hass, volume, entity_id=None):
-    """ Send the media player the command for volume down. """
+    """Send the media player the command for volume down."""
     data = {ATTR_MEDIA_VOLUME_LEVEL: volume}
 
     if entity_id:
@@ -168,44 +168,44 @@ def set_volume_level(hass, volume, entity_id=None):
 
 
 def media_play_pause(hass, entity_id=None):
-    """ Send the media player the command for play/pause. """
+    """Send the media player the command for play/pause."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_MEDIA_PLAY_PAUSE, data)
 
 
 def media_play(hass, entity_id=None):
-    """ Send the media player the command for play/pause. """
+    """Send the media player the command for play/pause."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_MEDIA_PLAY, data)
 
 
 def media_pause(hass, entity_id=None):
-    """ Send the media player the command for play/pause. """
+    """Send the media player the command for play/pause."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_MEDIA_PAUSE, data)
 
 
 def media_next_track(hass, entity_id=None):
-    """ Send the media player the command for next track. """
+    """Send the media player the command for next track."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_MEDIA_NEXT_TRACK, data)
 
 
 def media_previous_track(hass, entity_id=None):
-    """ Send the media player the command for prev track. """
+    """Send the media player the command for prev track."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     hass.services.call(DOMAIN, SERVICE_MEDIA_PREVIOUS_TRACK, data)
 
 
 def media_seek(hass, position, entity_id=None):
-    """ Send the media player the command to seek in current playing media. """
+    """Send the media player the command to seek in current playing media."""
     data = {ATTR_ENTITY_ID: entity_id} if entity_id else {}
     data[ATTR_MEDIA_SEEK_POSITION] = position
     hass.services.call(DOMAIN, SERVICE_MEDIA_SEEK, data)
 
 
 def play_media(hass, media_type, media_id, entity_id=None):
-    """ Send the media player the command for playing media. """
+    """Send the media player the command for playing media."""
     data = {"media_type": media_type, "media_id": media_id}
 
     if entity_id:
@@ -215,7 +215,7 @@ def play_media(hass, media_type, media_id, entity_id=None):
 
 
 def setup(hass, config):
-    """ Track states and offer events for media_players. """
+    """Track states and offer events for media_players."""
     component = EntityComponent(
         logging.getLogger(__name__), DOMAIN, hass, SCAN_INTERVAL,
         DISCOVERY_PLATFORMS)
@@ -226,7 +226,7 @@ def setup(hass, config):
         os.path.join(os.path.dirname(__file__), 'services.yaml'))
 
     def media_player_service_handler(service):
-        """ Maps services to methods on MediaPlayerDevice. """
+        """Map services to methods on MediaPlayerDevice."""
         target_players = component.extract_from_service(service)
 
         method = SERVICE_TO_METHOD[service.service]
@@ -242,7 +242,7 @@ def setup(hass, config):
                                descriptions.get(service))
 
     def volume_set_service(service):
-        """ Set specified volume on the media player. """
+        """Set specified volume on the media player."""
         target_players = component.extract_from_service(service)
 
         if ATTR_MEDIA_VOLUME_LEVEL not in service.data:
@@ -260,7 +260,7 @@ def setup(hass, config):
                            descriptions.get(SERVICE_VOLUME_SET))
 
     def volume_mute_service(service):
-        """ Mute (true) or unmute (false) the media player. """
+        """Mute (true) or unmute (false) the media player."""
         target_players = component.extract_from_service(service)
 
         if ATTR_MEDIA_VOLUME_MUTED not in service.data:
@@ -278,7 +278,7 @@ def setup(hass, config):
                            descriptions.get(SERVICE_VOLUME_MUTE))
 
     def media_seek_service(service):
-        """ Seek to a position. """
+        """Seek to a position."""
         target_players = component.extract_from_service(service)
 
         if ATTR_MEDIA_SEEK_POSITION not in service.data:
@@ -296,7 +296,7 @@ def setup(hass, config):
                            descriptions.get(SERVICE_MEDIA_SEEK))
 
     def play_media_service(service):
-        """ Plays specified media_id on the media player. """
+        """Play specified media_id on the media player."""
         media_type = service.data.get('media_type')
         media_id = service.data.get('media_id')
 
@@ -320,206 +320,205 @@ def setup(hass, config):
 
 
 class MediaPlayerDevice(Entity):
-    """ ABC for media player devices. """
+    """An abstract class for media player devices."""
+
     # pylint: disable=too-many-public-methods,no-self-use
-
     # Implement these for your media player
-
     @property
     def state(self):
-        """ State of the player. """
+        """State of the player."""
         return STATE_UNKNOWN
 
     @property
     def volume_level(self):
-        """ Volume level of the media player (0..1). """
+        """Volume level of the media player (0..1)."""
         return None
 
     @property
     def is_volume_muted(self):
-        """ Boolean if volume is currently muted. """
+        """Boolean if volume is currently muted."""
         return None
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         return None
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         return None
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         return None
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
+        """Image url of current playing media."""
         return None
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         return None
 
     @property
     def media_artist(self):
-        """ Artist of current playing media. (Music track only) """
+        """Artist of current playing media (Music track only)."""
         return None
 
     @property
     def media_album_name(self):
-        """ Album name of current playing media. (Music track only) """
+        """Album name of current playing media (Music track only)."""
         return None
 
     @property
     def media_album_artist(self):
-        """ Album arist of current playing media. (Music track only) """
+        """Album artist of current playing media (Music track only)."""
         return None
 
     @property
     def media_track(self):
-        """ Track number of current playing media. (Music track only) """
+        """Track number of current playing media (Music track only)."""
         return None
 
     @property
     def media_series_title(self):
-        """ Series title of current playing media. (TV Show only)"""
+        """The title of the series of current playing media (TV Show only)."""
         return None
 
     @property
     def media_season(self):
-        """ Season of current playing media. (TV Show only) """
+        """Season of current playing media (TV Show only)."""
         return None
 
     @property
     def media_episode(self):
-        """ Episode of current playing media. (TV Show only) """
+        """Episode of current playing media (TV Show only)."""
         return None
 
     @property
     def media_channel(self):
-        """ Channel currently playing. """
+        """Channel currently playing."""
         return None
 
     @property
     def media_playlist(self):
-        """ Title of Playlist currently playing. """
+        """Title of Playlist currently playing."""
         return None
 
     @property
     def app_id(self):
-        """  ID of the current running app. """
+        """ID of the current running app."""
         return None
 
     @property
     def app_name(self):
-        """  Name of the current running app. """
+        """Name of the current running app."""
         return None
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return 0
 
     def turn_on(self):
-        """ turn the media player on. """
+        """Turn the media player on."""
         raise NotImplementedError()
 
     def turn_off(self):
-        """ turn the media player off. """
+        """Turn the media player off."""
         raise NotImplementedError()
 
     def mute_volume(self, mute):
-        """ mute the volume. """
+        """Mute the volume."""
         raise NotImplementedError()
 
     def set_volume_level(self, volume):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         raise NotImplementedError()
 
     def media_play(self):
-        """ Send play commmand. """
+        """Send play commmand."""
         raise NotImplementedError()
 
     def media_pause(self):
-        """ Send pause command. """
+        """Send pause command."""
         raise NotImplementedError()
 
     def media_previous_track(self):
-        """ Send previous track command. """
+        """Send previous track command."""
         raise NotImplementedError()
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         raise NotImplementedError()
 
     def media_seek(self, position):
-        """ Send seek command. """
+        """Send seek command."""
         raise NotImplementedError()
 
     def play_media(self, media_type, media_id):
-        """ Plays a piece of media. """
+        """Play a piece of media."""
         raise NotImplementedError()
 
     # No need to overwrite these.
     @property
     def support_pause(self):
-        """ Boolean if pause is supported. """
+        """Boolean if pause is supported."""
         return bool(self.supported_media_commands & SUPPORT_PAUSE)
 
     @property
     def support_seek(self):
-        """ Boolean if seek is supported. """
+        """Boolean if seek is supported."""
         return bool(self.supported_media_commands & SUPPORT_SEEK)
 
     @property
     def support_volume_set(self):
-        """ Boolean if setting volume is supported. """
+        """Boolean if setting volume is supported."""
         return bool(self.supported_media_commands & SUPPORT_VOLUME_SET)
 
     @property
     def support_volume_mute(self):
-        """ Boolean if muting volume is supported. """
+        """Boolean if muting volume is supported."""
         return bool(self.supported_media_commands & SUPPORT_VOLUME_MUTE)
 
     @property
     def support_previous_track(self):
-        """ Boolean if previous track command supported. """
+        """Boolean if previous track command supported."""
         return bool(self.supported_media_commands & SUPPORT_PREVIOUS_TRACK)
 
     @property
     def support_next_track(self):
-        """ Boolean if next track command supported. """
+        """Boolean if next track command supported."""
         return bool(self.supported_media_commands & SUPPORT_NEXT_TRACK)
 
     @property
     def support_play_media(self):
-        """ Boolean if play media command supported. """
+        """Boolean if play media command supported."""
         return bool(self.supported_media_commands & SUPPORT_PLAY_MEDIA)
 
     def toggle(self):
-        """ Toggles the power on the media player. """
+        """Toggle the power on the media player."""
         if self.state in [STATE_OFF, STATE_IDLE]:
             self.turn_on()
         else:
             self.turn_off()
 
     def volume_up(self):
-        """ volume_up media player. """
+        """volume_up media player."""
         if self.volume_level < 1:
             self.set_volume_level(min(1, self.volume_level + .1))
 
     def volume_down(self):
-        """ volume_down media player. """
+        """volume_down media player."""
         if self.volume_level > 0:
             self.set_volume_level(max(0, self.volume_level - .1))
 
     def media_play_pause(self):
-        """ media_play_pause media player. """
+        """media_play_pause media player."""
         if self.state == STATE_PLAYING:
             self.media_pause()
         else:
@@ -527,12 +526,12 @@ class MediaPlayerDevice(Entity):
 
     @property
     def entity_picture(self):
-        """Return image of the media playing."""
+        """Return the image of the media playing."""
         return None if self.state == STATE_OFF else self.media_image_url
 
     @property
     def state_attributes(self):
-        """ Return the state attributes. """
+        """Return the state attributes."""
         if self.state == STATE_OFF:
             state_attr = {
                 ATTR_SUPPORTED_MEDIA_COMMANDS: self.supported_media_commands,
diff --git a/homeassistant/components/media_player/cast.py b/homeassistant/components/media_player/cast.py
index eed72b7aa93..022a2d2d762 100644
--- a/homeassistant/components/media_player/cast.py
+++ b/homeassistant/components/media_player/cast.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.chromecast
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides functionality to interact with Cast devices on the network.
+Provide functionality to interact with Cast devices on the network.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.cast/
@@ -31,7 +29,7 @@ DEFAULT_PORT = 8009
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the cast platform. """
+    """Setup the cast platform."""
     import pychromecast
     logger = logging.getLogger(__name__)
 
@@ -70,12 +68,12 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class CastDevice(MediaPlayerDevice):
-    """ Represents a Cast device on the network. """
+    """Representation of a Cast device on the network."""
 
     # pylint: disable=abstract-method
     # pylint: disable=too-many-public-methods
-
     def __init__(self, host, port):
+        """Initialize the Cast device."""
         import pychromecast
         self.cast = pychromecast.Chromecast(host, port)
 
@@ -86,22 +84,20 @@ class CastDevice(MediaPlayerDevice):
         self.cast_status = self.cast.status
         self.media_status = self.cast.media_controller.status
 
-    # Entity properties and methods
-
     @property
     def should_poll(self):
+        """No polling needed."""
         return False
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self.cast.device.friendly_name
 
     # MediaPlayerDevice properties and methods
-
     @property
     def state(self):
-        """ State of the player. """
+        """Return the state of the player."""
         if self.media_status is None:
             return STATE_UNKNOWN
         elif self.media_status.player_is_playing:
@@ -117,22 +113,22 @@ class CastDevice(MediaPlayerDevice):
 
     @property
     def volume_level(self):
-        """ Volume level of the media player (0..1). """
+        """Volume level of the media player (0..1)."""
         return self.cast_status.volume_level if self.cast_status else None
 
     @property
     def is_volume_muted(self):
-        """ Boolean if volume is currently muted. """
+        """Boolean if volume is currently muted."""
         return self.cast_status.volume_muted if self.cast_status else None
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         return self.media_status.content_id if self.media_status else None
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         if self.media_status is None:
             return None
         elif self.media_status.media_is_tvshow:
@@ -145,12 +141,12 @@ class CastDevice(MediaPlayerDevice):
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         return self.media_status.duration if self.media_status else None
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
+        """Image url of current playing media."""
         if self.media_status is None:
             return None
 
@@ -160,61 +156,61 @@ class CastDevice(MediaPlayerDevice):
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         return self.media_status.title if self.media_status else None
 
     @property
     def media_artist(self):
-        """ Artist of current playing media. (Music track only) """
+        """Artist of current playing media (Music track only)."""
         return self.media_status.artist if self.media_status else None
 
     @property
     def media_album(self):
-        """ Album of current playing media. (Music track only) """
+        """Album of current playing media (Music track only)."""
         return self.media_status.album_name if self.media_status else None
 
     @property
     def media_album_artist(self):
-        """ Album arist of current playing media. (Music track only) """
+        """Album arist of current playing media (Music track only)."""
         return self.media_status.album_artist if self.media_status else None
 
     @property
     def media_track(self):
-        """ Track number of current playing media. (Music track only) """
+        """Track number of current playing media (Music track only)."""
         return self.media_status.track if self.media_status else None
 
     @property
     def media_series_title(self):
-        """ Series title of current playing media. (TV Show only)"""
+        """The title of the series of current playing media (TV Show only)."""
         return self.media_status.series_title if self.media_status else None
 
     @property
     def media_season(self):
-        """ Season of current playing media. (TV Show only) """
+        """Season of current playing media (TV Show only)."""
         return self.media_status.season if self.media_status else None
 
     @property
     def media_episode(self):
-        """ Episode of current playing media. (TV Show only) """
+        """Episode of current playing media (TV Show only)."""
         return self.media_status.episode if self.media_status else None
 
     @property
     def app_id(self):
-        """  ID of the current running app. """
+        """Return the ID of the current running app."""
         return self.cast.app_id
 
     @property
     def app_name(self):
-        """  Name of the current running app. """
+        """Name of the current running app."""
         return self.cast.app_display_name
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_CAST
 
     def turn_on(self):
-        """ Turns on the ChromeCast. """
+        """Turn on the ChromeCast."""
         # The only way we can turn the Chromecast is on is by launching an app
         if not self.cast.status or not self.cast.status.is_active_input:
             import pychromecast
@@ -226,49 +222,48 @@ class CastDevice(MediaPlayerDevice):
                 CAST_SPLASH, pychromecast.STREAM_TYPE_BUFFERED)
 
     def turn_off(self):
-        """ Turns Chromecast off. """
+        """Turn Chromecast off."""
         self.cast.quit_app()
 
     def mute_volume(self, mute):
-        """ mute the volume. """
+        """Mute the volume."""
         self.cast.set_volume_muted(mute)
 
     def set_volume_level(self, volume):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         self.cast.set_volume(volume)
 
     def media_play(self):
-        """ Send play commmand. """
+        """Send play commmand."""
         self.cast.media_controller.play()
 
     def media_pause(self):
-        """ Send pause command. """
+        """Send pause command."""
         self.cast.media_controller.pause()
 
     def media_previous_track(self):
-        """ Send previous track command. """
+        """Send previous track command."""
         self.cast.media_controller.rewind()
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self.cast.media_controller.skip()
 
     def media_seek(self, position):
-        """ Seek the media to a specific location. """
+        """Seek the media to a specific location."""
         self.cast.media_controller.seek(position)
 
     def play_media(self, media_type, media_id):
-        """ Plays media from a URL """
+        """Play media from a URL."""
         self.cast.media_controller.play_media(media_id, media_type)
 
-    # implementation of chromecast status_listener methods
-
+    # Implementation of chromecast status_listener methods
     def new_cast_status(self, status):
-        """ Called when a new cast status is received. """
+        """Called when a new cast status is received."""
         self.cast_status = status
         self.update_ha_state()
 
     def new_media_status(self, status):
-        """ Called when a new media status is received. """
+        """Called when a new media status is received."""
         self.media_status = status
         self.update_ha_state()
diff --git a/homeassistant/components/media_player/demo.py b/homeassistant/components/media_player/demo.py
index 04fe7bb49c3..913d41c27ba 100644
--- a/homeassistant/components/media_player/demo.py
+++ b/homeassistant/components/media_player/demo.py
@@ -14,7 +14,7 @@ from homeassistant.const import STATE_OFF, STATE_PAUSED, STATE_PLAYING
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """Setup the media palyer demo platform."""
+    """Setup the media player demo platform."""
     add_devices([
         DemoYoutubePlayer(
             'Living Room', 'eyU3bRy2x44',
@@ -39,10 +39,12 @@ NETFLIX_PLAYER_SUPPORT = \
 
 
 class AbstractDemoPlayer(MediaPlayerDevice):
-    """A demo media players"""
+    """A demo media players."""
+
     # We only implement the methods that we support
     # pylint: disable=abstract-method
     def __init__(self, name):
+        """Initialize the demo device."""
         self._name = name
         self._player_state = STATE_PLAYING
         self._volume_level = 1.0
@@ -106,9 +108,11 @@ class AbstractDemoPlayer(MediaPlayerDevice):
 
 class DemoYoutubePlayer(AbstractDemoPlayer):
     """A Demo media player that only supports YouTube."""
+
     # We only implement the methods that we support
     # pylint: disable=abstract-method
     def __init__(self, name, youtube_id=None, media_title=None):
+        """Initialize the demo device."""
         super().__init__(name)
         self.youtube_id = youtube_id
         self._media_title = media_title
@@ -125,7 +129,7 @@ class DemoYoutubePlayer(AbstractDemoPlayer):
 
     @property
     def media_duration(self):
-        """ Return the duration of current playing media in seconds."""
+        """Return the duration of current playing media in seconds."""
         return 360
 
     @property
@@ -145,7 +149,7 @@ class DemoYoutubePlayer(AbstractDemoPlayer):
 
     @property
     def supported_media_commands(self):
-        """Flags of media commands that are supported."""
+        """Flag of media commands that are supported."""
         return YOUTUBE_PLAYER_SUPPORT
 
     def play_media(self, media_type, media_id):
@@ -156,6 +160,7 @@ class DemoYoutubePlayer(AbstractDemoPlayer):
 
 class DemoMusicPlayer(AbstractDemoPlayer):
     """A Demo media player that only supports YouTube."""
+
     # We only implement the methods that we support
     # pylint: disable=abstract-method
     tracks = [
@@ -181,6 +186,7 @@ class DemoMusicPlayer(AbstractDemoPlayer):
     ]
 
     def __init__(self):
+        """Initialize the demo device."""
         super().__init__('Walkman')
         self._cur_track = 0
 
@@ -222,14 +228,12 @@ class DemoMusicPlayer(AbstractDemoPlayer):
 
     @property
     def media_track(self):
-        """
-        Return the track number of current playing media (Music track only).
-        """
+        """Return the track number of current media (Music track only)."""
         return self._cur_track + 1
 
     @property
     def supported_media_commands(self):
-        """Flags of media commands that are supported."""
+        """Flag of media commands that are supported."""
         support = MUSIC_PLAYER_SUPPORT
 
         if self._cur_track > 0:
@@ -255,9 +259,11 @@ class DemoMusicPlayer(AbstractDemoPlayer):
 
 class DemoTVShowPlayer(AbstractDemoPlayer):
     """A Demo media player that only supports YouTube."""
+
     # We only implement the methods that we support
     # pylint: disable=abstract-method
     def __init__(self):
+        """Initialize the demo device."""
         super().__init__('Lounge room')
         self._cur_episode = 1
         self._episode_count = 13
diff --git a/homeassistant/components/media_player/denon.py b/homeassistant/components/media_player/denon.py
index 2853dda90ac..b4bcc9ae5ba 100644
--- a/homeassistant/components/media_player/denon.py
+++ b/homeassistant/components/media_player/denon.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.denon
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides an interface to Denon Network Receivers.
+Support for Denon Network Receivers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.denon/
@@ -23,7 +21,7 @@ SUPPORT_DENON = SUPPORT_PAUSE | SUPPORT_VOLUME_SET | SUPPORT_VOLUME_MUTE | \
 
 
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the Denon platform. """
+    """Setup the Denon platform."""
     if not config.get(CONF_HOST):
         _LOGGER.error(
             "Missing required configuration items in %s: %s",
@@ -43,11 +41,11 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class DenonDevice(MediaPlayerDevice):
-    """ Represents a Denon device. """
+    """Representation of a Denon device."""
 
     # pylint: disable=too-many-public-methods, abstract-method
-
     def __init__(self, name, host):
+        """Initialize the Denon device."""
         self._name = name
         self._host = host
         self._pwstate = "PWSTANDBY"
@@ -57,18 +55,19 @@ class DenonDevice(MediaPlayerDevice):
 
     @classmethod
     def telnet_request(cls, telnet, command):
-        """ Executes `command` and returns the response. """
+        """Execute `command` and return the response."""
         telnet.write(command.encode("ASCII") + b"\r")
         return telnet.read_until(b"\r", timeout=0.2).decode("ASCII").strip()
 
     def telnet_command(self, command):
-        """ Establishes a telnet connection and sends `command`. """
+        """Establish a telnet connection and sends `command`."""
         telnet = telnetlib.Telnet(self._host)
         telnet.write(command.encode("ASCII") + b"\r")
         telnet.read_very_eager()  # skip response
         telnet.close()
 
     def update(self):
+        """Get the latest details from the device."""
         try:
             telnet = telnetlib.Telnet(self._host)
         except ConnectionRefusedError:
@@ -88,12 +87,12 @@ class DenonDevice(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self._name
 
     @property
     def state(self):
-        """ Returns the state of the device. """
+        """Return the state of the device."""
         if self._pwstate == "PWSTANDBY":
             return STATE_OFF
         if self._pwstate == "PWON":
@@ -103,60 +102,61 @@ class DenonDevice(MediaPlayerDevice):
 
     @property
     def volume_level(self):
-        """ Volume level of the media player (0..1). """
+        """Volume level of the media player (0..1)."""
         return self._volume
 
     @property
     def is_volume_muted(self):
-        """ Boolean if volume is currently muted. """
+        """Boolean if volume is currently muted."""
         return self._muted
 
     @property
     def media_title(self):
-        """ Current media source. """
+        """Current media source."""
         return self._mediasource
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_DENON
 
     def turn_off(self):
-        """ turn_off media player. """
+        """Turn off media player."""
         self.telnet_command("PWSTANDBY")
 
     def volume_up(self):
-        """ volume_up media player. """
+        """Volume up media player."""
         self.telnet_command("MVUP")
 
     def volume_down(self):
-        """ volume_down media player. """
+        """Volume down media player."""
         self.telnet_command("MVDOWN")
 
     def set_volume_level(self, volume):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         # 60dB max
         self.telnet_command("MV" + str(round(volume * 60)).zfill(2))
 
     def mute_volume(self, mute):
-        """ mute (true) or unmute (false) media player. """
+        """Mute (true) or unmute (false) media player."""
         self.telnet_command("MU" + ("ON" if mute else "OFF"))
 
     def media_play(self):
-        """ media_play media player. """
+        """Play media media player."""
         self.telnet_command("NS9A")
 
     def media_pause(self):
-        """ media_pause media player. """
+        """Pause media player."""
         self.telnet_command("NS9B")
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send the next track command."""
         self.telnet_command("NS9D")
 
     def media_previous_track(self):
+        """Send the previous track command."""
         self.telnet_command("NS9E")
 
     def turn_on(self):
-        """ turn the media player on. """
+        """Turn the media player on."""
         self.telnet_command("PWON")
diff --git a/homeassistant/components/media_player/firetv.py b/homeassistant/components/media_player/firetv.py
index e151f1d516f..02b456a207c 100644
--- a/homeassistant/components/media_player/firetv.py
+++ b/homeassistant/components/media_player/firetv.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.firetv
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides functionality to interact with FireTV devices.
+Support for functionality to interact with FireTV devices.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.firetv/
@@ -31,7 +29,7 @@ _LOGGER = logging.getLogger(__name__)
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the FireTV platform. """
+    """Setup the FireTV platform."""
     host = config.get('host', 'localhost:5556')
     device_id = config.get('device', 'default')
     try:
@@ -54,7 +52,7 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class FireTV(object):
-    """ firetv-server client.
+    """The firetv-server client.
 
     Should a native Python 3 ADB module become available, python-firetv can
     support Python 3, it can be added as a dependency, and this class can be
@@ -65,12 +63,13 @@ class FireTV(object):
     """
 
     def __init__(self, host, device_id):
+        """Initialize the FireTV server."""
         self.host = host
         self.device_id = device_id
 
     @property
     def state(self):
-        """ Get the device state. An exception means UNKNOWN state. """
+        """Get the device state. An exception means UNKNOWN state."""
         try:
             response = requests.get(
                 DEVICE_STATE_URL.format(
@@ -85,7 +84,7 @@ class FireTV(object):
             return STATE_UNKNOWN
 
     def action(self, action_id):
-        """ Perform an action on the device. """
+        """Perform an action on the device."""
         try:
             requests.get(
                 DEVICE_ACTION_URL.format(
@@ -101,37 +100,37 @@ class FireTV(object):
 
 
 class FireTVDevice(MediaPlayerDevice):
-    """ Represents an Amazon Fire TV device on the network. """
+    """Representation of an Amazon Fire TV device on the network."""
 
     # pylint: disable=abstract-method
-
     def __init__(self, host, device, name):
+        """Initialize the FireTV device."""
         self._firetv = FireTV(host, device)
         self._name = name
         self._state = STATE_UNKNOWN
 
     @property
     def name(self):
-        """ Get the device name. """
+        """Return the device name."""
         return self._name
 
     @property
     def should_poll(self):
-        """ Device should be polled. """
+        """Device should be polled."""
         return True
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_FIRETV
 
     @property
     def state(self):
-        """ State of the player. """
+        """Return the state of the player."""
         return self._state
 
     def update(self):
-        """ Update device state. """
+        """Get the latest date and update device state."""
         self._state = {
             'idle': STATE_IDLE,
             'off': STATE_OFF,
@@ -142,37 +141,37 @@ class FireTVDevice(MediaPlayerDevice):
         }.get(self._firetv.state, STATE_UNKNOWN)
 
     def turn_on(self):
-        """ Turns on the device. """
+        """Turn on the device."""
         self._firetv.action('turn_on')
 
     def turn_off(self):
-        """ Turns off the device. """
+        """Turn off the device."""
         self._firetv.action('turn_off')
 
     def media_play(self):
-        """ Send play command. """
+        """Send play command."""
         self._firetv.action('media_play')
 
     def media_pause(self):
-        """ Send pause command. """
+        """Send pause command."""
         self._firetv.action('media_pause')
 
     def media_play_pause(self):
-        """ Send play/pause command. """
+        """Send play/pause command."""
         self._firetv.action('media_play_pause')
 
     def volume_up(self):
-        """ Send volume up command. """
+        """Send volume up command."""
         self._firetv.action('volume_up')
 
     def volume_down(self):
-        """ Send volume down command. """
+        """Send volume down command."""
         self._firetv.action('volume_down')
 
     def media_previous_track(self):
-        """ Send previous track command (results in rewind). """
+        """Send previous track command (results in rewind)."""
         self._firetv.action('media_previous')
 
     def media_next_track(self):
-        """ Send next track command (results in fast-forward). """
+        """Send next track command (results in fast-forward)."""
         self._firetv.action('media_next')
diff --git a/homeassistant/components/media_player/itunes.py b/homeassistant/components/media_player/itunes.py
index 584a692bd57..9418d1c5703 100644
--- a/homeassistant/components/media_player/itunes.py
+++ b/homeassistant/components/media_player/itunes.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.itunes
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides an interface to iTunes API.
+Support for interfacing to iTunes API.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.itunes/
@@ -30,22 +28,23 @@ DOMAIN = 'itunes'
 
 
 class Itunes(object):
-    """ itunes-api client. """
+    """iTunes API client."""
 
     def __init__(self, host, port):
+        """Initialize the iTunes device."""
         self.host = host
         self.port = port
 
     @property
     def _base_url(self):
-        """ Returns the base url for endpoints. """
+        """Return the base url for endpoints."""
         if self.port:
             return self.host + ":" + str(self.port)
         else:
             return self.host
 
     def _request(self, method, path, params=None):
-        """ Makes the actual request and returns the parsed response. """
+        """Make the actual request and returns the parsed response."""
         url = self._base_url + path
 
         try:
@@ -65,39 +64,39 @@ class Itunes(object):
             return {'player_state': 'offline'}
 
     def _command(self, named_command):
-        """ Makes a request for a controlling command. """
+        """Make a request for a controlling command."""
         return self._request('PUT', '/' + named_command)
 
     def now_playing(self):
-        """ Returns the current state. """
+        """Return the current state."""
         return self._request('GET', '/now_playing')
 
     def set_volume(self, level):
-        """ Sets the volume and returns the current state, level 0-100. """
+        """Set the volume and returns the current state, level 0-100."""
         return self._request('PUT', '/volume', {'level': level})
 
     def set_muted(self, muted):
-        """ Mutes and returns the current state, muted True or False. """
+        """Mute and returns the current state, muted True or False."""
         return self._request('PUT', '/mute', {'muted': muted})
 
     def play(self):
-        """ Sets playback to play and returns the current state. """
+        """Set playback to play and returns the current state."""
         return self._command('play')
 
     def pause(self):
-        """ Sets playback to paused and returns the current state. """
+        """Set playback to paused and returns the current state."""
         return self._command('pause')
 
     def next(self):
-        """ Skips to the next track and returns the current state. """
+        """Skip to the next track and returns the current state."""
         return self._command('next')
 
     def previous(self):
-        """ Skips back and returns the current state. """
+        """Skip back and returns the current state."""
         return self._command('previous')
 
     def play_playlist(self, playlist_id_or_name):
-        """ Sets a playlist to be current and returns the current state. """
+        """Set a playlist to be current and returns the current state."""
         response = self._request('GET', '/playlists')
         playlists = response.get('playlists', [])
 
@@ -111,25 +110,25 @@ class Itunes(object):
             return self._request('PUT', path)
 
     def artwork_url(self):
-        """ Returns a URL of the current track's album art. """
+        """Return a URL of the current track's album art."""
         return self._base_url + '/artwork'
 
     def airplay_devices(self):
-        """ Returns a list of AirPlay devices. """
+        """Return a list of AirPlay devices."""
         return self._request('GET', '/airplay_devices')
 
     def airplay_device(self, device_id):
-        """ Returns an AirPlay device. """
+        """Return an AirPlay device."""
         return self._request('GET', '/airplay_devices/' + device_id)
 
     def toggle_airplay_device(self, device_id, toggle):
-        """ Toggles airplay device on or off, id, toggle True or False. """
+        """Toggle airplay device on or off, id, toggle True or False."""
         command = 'on' if toggle else 'off'
         path = '/airplay_devices/' + device_id + '/' + command
         return self._request('PUT', path)
 
     def set_volume_airplay_device(self, device_id, level):
-        """ Sets volume, returns current state of device, id,level 0-100. """
+        """Set volume, returns current state of device, id,level 0-100."""
         path = '/airplay_devices/' + device_id + '/volume'
         return self._request('PUT', path, {'level': level})
 
@@ -137,8 +136,7 @@ class Itunes(object):
 # pylint: disable=unused-argument, abstract-method
 # pylint: disable=too-many-instance-attributes
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the itunes platform. """
-
+    """Setup the itunes platform."""
     add_devices([
         ItunesDevice(
             config.get('name', 'iTunes'),
@@ -150,10 +148,11 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class ItunesDevice(MediaPlayerDevice):
-    """ Represents a iTunes-API instance. """
+    """Representation of an iTunes API instance."""
 
     # pylint: disable=too-many-public-methods
     def __init__(self, name, host, port, add_devices):
+        """Initialize the iTunes device."""
         self._name = name
         self._host = host
         self._port = port
@@ -176,7 +175,7 @@ class ItunesDevice(MediaPlayerDevice):
         self.update()
 
     def update_state(self, state_hash):
-        """ Update all the state properties with the passed in dictionary. """
+        """Update all the state properties with the passed in dictionary."""
         self.player_state = state_hash.get('player_state', None)
 
         self.current_volume = state_hash.get('volume', 0)
@@ -189,13 +188,12 @@ class ItunesDevice(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self._name
 
     @property
     def state(self):
-        """ Returns the state of the device. """
-
+        """Return the state of the device."""
         if self.player_state == 'offline' or self.player_state is None:
             return 'offline'
 
@@ -211,7 +209,7 @@ class ItunesDevice(MediaPlayerDevice):
             return STATE_PLAYING
 
     def update(self):
-        """ Retrieve latest state. """
+        """Retrieve latest state."""
         now_playing = self.client.now_playing()
         self.update_state(now_playing)
 
@@ -239,28 +237,27 @@ class ItunesDevice(MediaPlayerDevice):
 
     @property
     def is_volume_muted(self):
-        """ Boolean if volume is currently muted. """
+        """Boolean if volume is currently muted."""
         return self.muted
 
     @property
     def volume_level(self):
-        """ Volume level of the media player (0..1). """
+        """Volume level of the media player (0..1)."""
         return self.current_volume/100.0
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         return self.content_id
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         return MEDIA_TYPE_MUSIC
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
-
+        """Image url of current playing media."""
         if self.player_state in (STATE_PLAYING, STATE_IDLE, STATE_PAUSED) and \
            self.current_title is not None:
             return self.client.artwork_url()
@@ -270,76 +267,74 @@ class ItunesDevice(MediaPlayerDevice):
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         return self.current_title
 
     @property
     def media_artist(self):
-        """ Artist of current playing media. (Music track only) """
+        """Artist of current playing media (Music track only)."""
         return self.current_artist
 
     @property
     def media_album_name(self):
-        """ Album of current playing media. (Music track only) """
+        """Album of current playing media (Music track only)."""
         return self.current_album
 
     @property
     def media_playlist(self):
-        """ Title of the currently playing playlist. """
+        """Title of the currently playing playlist."""
         return self.current_playlist
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_ITUNES
 
     def set_volume_level(self, volume):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         response = self.client.set_volume(int(volume * 100))
         self.update_state(response)
 
     def mute_volume(self, mute):
-        """ mute (true) or unmute (false) media player. """
+        """Mute (true) or unmute (false) media player."""
         response = self.client.set_muted(mute)
         self.update_state(response)
 
     def media_play(self):
-        """ media_play media player. """
+        """Send media_play command to media player."""
         response = self.client.play()
         self.update_state(response)
 
     def media_pause(self):
-        """ media_pause media player. """
+        """Send media_pause command to media player."""
         response = self.client.pause()
         self.update_state(response)
 
     def media_next_track(self):
-        """ media_next media player. """
+        """Send media_next command to media player."""
         response = self.client.next()
         self.update_state(response)
 
     def media_previous_track(self):
-        """ media_previous media player. """
+        """Send media_previous command media player."""
         response = self.client.previous()
         self.update_state(response)
 
     def play_media(self, media_type, media_id):
-        """ play_media media player. """
+        """Send the play_media command to the media player."""
         if media_type == MEDIA_TYPE_PLAYLIST:
             response = self.client.play_playlist(media_id)
             self.update_state(response)
 
 
 class AirPlayDevice(MediaPlayerDevice):
-    """ Represents an AirPlay device via an iTunes-API instance. """
+    """Representation an AirPlay device via an iTunes API instance."""
 
     # pylint: disable=too-many-public-methods
-
     def __init__(self, device_id, client):
+        """Initialize the AirPlay device."""
         self._id = device_id
-
         self.client = client
-
         self.device_name = "AirPlay"
         self.kind = None
         self.active = False
@@ -350,8 +345,7 @@ class AirPlayDevice(MediaPlayerDevice):
         self.player_state = None
 
     def update_state(self, state_hash):
-        """ Update all the state properties with the passed in dictionary. """
-
+        """Update all the state properties with the passed in dictionary."""
         if 'player_state' in state_hash:
             self.player_state = state_hash.get('player_state', None)
 
@@ -379,12 +373,12 @@ class AirPlayDevice(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self.device_name
 
     @property
     def icon(self):
-        """ Icon to use in the frontend, if any. """
+        """Return the icon to use in the frontend, if any."""
         if self.selected is True:
             return "mdi:volume-high"
         else:
@@ -392,44 +386,45 @@ class AirPlayDevice(MediaPlayerDevice):
 
     @property
     def state(self):
-        """ Returns the state of the device. """
-
+        """Return the state of the device."""
         if self.selected is True:
             return STATE_ON
         else:
             return STATE_OFF
 
     def update(self):
-        """ Retrieve latest state. """
+        """Retrieve latest state."""
 
     @property
     def volume_level(self):
+        """Return the volume."""
         return float(self.volume)/100.0
 
     @property
     def media_content_type(self):
+        """Flag of media content that is supported."""
         return MEDIA_TYPE_MUSIC
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_AIRPLAY
 
     def set_volume_level(self, volume):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         volume = int(volume * 100)
         response = self.client.set_volume_airplay_device(self._id, volume)
         self.update_state(response)
 
     def turn_on(self):
-        """ Select AirPlay. """
+        """Select AirPlay."""
         self.update_state({"selected": True})
         self.update_ha_state()
         response = self.client.toggle_airplay_device(self._id, True)
         self.update_state(response)
 
     def turn_off(self):
-        """ Deselect AirPlay. """
+        """Deselect AirPlay."""
         self.update_state({"selected": False})
         self.update_ha_state()
         response = self.client.toggle_airplay_device(self._id, False)
diff --git a/homeassistant/components/media_player/kodi.py b/homeassistant/components/media_player/kodi.py
index f7a7e9cf53a..6184608a9e8 100644
--- a/homeassistant/components/media_player/kodi.py
+++ b/homeassistant/components/media_player/kodi.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.kodi
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides an interface to the XBMC/Kodi JSON-RPC API
+Support for interfacing with the XBMC/Kodi JSON-RPC API.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.kodi/
@@ -23,8 +21,7 @@ SUPPORT_KODI = SUPPORT_PAUSE | SUPPORT_VOLUME_SET | SUPPORT_VOLUME_MUTE | \
 
 
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the kodi platform. """
-
+    """Setup the Kodi platform."""
     url = '{}:{}'.format(config.get('host'), config.get('port', '8080'))
 
     jsonrpc_url = config.get('url')  # deprecated
@@ -42,11 +39,11 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class KodiDevice(MediaPlayerDevice):
-    """ Represents a XBMC/Kodi device. """
+    """Representation of a XBMC/Kodi device."""
 
     # pylint: disable=too-many-public-methods, abstract-method
-
     def __init__(self, name, url, auth=None):
+        """Initialize the Kodi device."""
         import jsonrpc_requests
         self._name = name
         self._url = url
@@ -61,11 +58,11 @@ class KodiDevice(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self._name
 
     def _get_players(self):
-        """ Returns the active player objects or None """
+        """Return the active player objects or None."""
         import jsonrpc_requests
         try:
             return self._server.Player.GetActivePlayers()
@@ -76,7 +73,7 @@ class KodiDevice(MediaPlayerDevice):
 
     @property
     def state(self):
-        """ Returns the state of the device. """
+        """Return the state of the device."""
         if self._players is None:
             return STATE_OFF
 
@@ -89,7 +86,7 @@ class KodiDevice(MediaPlayerDevice):
             return STATE_PLAYING
 
     def update(self):
-        """ Retrieve latest state. """
+        """Retrieve latest state."""
         self._players = self._get_players()
 
         if self._players is not None and len(self._players) > 0:
@@ -117,31 +114,31 @@ class KodiDevice(MediaPlayerDevice):
 
     @property
     def volume_level(self):
-        """ Volume level of the media player (0..1). """
+        """Volume level of the media player (0..1)."""
         if self._app_properties is not None:
             return self._app_properties['volume'] / 100.0
 
     @property
     def is_volume_muted(self):
-        """ Boolean if volume is currently muted. """
+        """Boolean if volume is currently muted."""
         if self._app_properties is not None:
             return self._app_properties['muted']
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         if self._item is not None:
             return self._item.get('uniqueid', None)
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         if self._players is not None and len(self._players) > 0:
             return self._players[0]['type']
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         if self._properties is not None:
             total_time = self._properties['totaltime']
 
@@ -152,12 +149,12 @@ class KodiDevice(MediaPlayerDevice):
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
+        """Image url of current playing media."""
         if self._item is not None:
             return self._get_image_url()
 
     def _get_image_url(self):
-        """ Helper function that parses the thumbnail URLs used by Kodi. """
+        """Helper function that parses the thumbnail URLs used by Kodi."""
         url_components = urllib.parse.urlparse(self._item['thumbnail'])
 
         if url_components.scheme == 'image':
@@ -167,7 +164,7 @@ class KodiDevice(MediaPlayerDevice):
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         # find a string we can use as a title
         if self._item is not None:
             return self._item.get(
@@ -180,36 +177,36 @@ class KodiDevice(MediaPlayerDevice):
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_KODI
 
     def turn_off(self):
-        """ turn_off media player. """
+        """Turn off media player."""
         self._server.System.Shutdown()
         self.update_ha_state()
 
     def volume_up(self):
-        """ volume_up media player. """
+        """Volume up the media player."""
         assert self._server.Input.ExecuteAction('volumeup') == 'OK'
         self.update_ha_state()
 
     def volume_down(self):
-        """ volume_down media player. """
+        """Volume down the media player."""
         assert self._server.Input.ExecuteAction('volumedown') == 'OK'
         self.update_ha_state()
 
     def set_volume_level(self, volume):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         self._server.Application.SetVolume(int(volume * 100))
         self.update_ha_state()
 
     def mute_volume(self, mute):
-        """ mute (true) or unmute (false) media player. """
+        """Mute (true) or unmute (false) media player."""
         self._server.Application.SetMute(mute)
         self.update_ha_state()
 
     def _set_play_state(self, state):
-        """ Helper method for play/pause/toggle. """
+        """Helper method for play/pause/toggle."""
         players = self._get_players()
 
         if len(players) != 0:
@@ -218,19 +215,19 @@ class KodiDevice(MediaPlayerDevice):
         self.update_ha_state()
 
     def media_play_pause(self):
-        """ media_play_pause media player. """
+        """Pause media on media player."""
         self._set_play_state('toggle')
 
     def media_play(self):
-        """ media_play media player. """
+        """Play media."""
         self._set_play_state(True)
 
     def media_pause(self):
-        """ media_pause media player. """
+        """Pause the media player."""
         self._set_play_state(False)
 
     def _goto(self, direction):
-        """ Helper method used for previous/next track. """
+        """Helper method used for previous/next track."""
         players = self._get_players()
 
         if len(players) != 0:
@@ -239,18 +236,18 @@ class KodiDevice(MediaPlayerDevice):
         self.update_ha_state()
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self._goto('next')
 
     def media_previous_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         # first seek to position 0, Kodi seems to go to the beginning
         # of the current track current track is not at the beginning
         self.media_seek(0)
         self._goto('previous')
 
     def media_seek(self, position):
-        """ Send seek command. """
+        """Send seek command."""
         players = self._get_players()
 
         time = {}
diff --git a/homeassistant/components/media_player/mpd.py b/homeassistant/components/media_player/mpd.py
index a4a6c0cac61..526cfe8b45b 100644
--- a/homeassistant/components/media_player/mpd.py
+++ b/homeassistant/components/media_player/mpd.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.mpd
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides functionality to interact with a Music Player Daemon.
+Support to interact with a Music Player Daemon.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.mpd/
@@ -24,8 +22,7 @@ SUPPORT_MPD = SUPPORT_PAUSE | SUPPORT_VOLUME_SET | SUPPORT_TURN_OFF | \
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the MPD platform. """
-
+    """Setup the MPD platform."""
     daemon = config.get('server', None)
     port = config.get('port', 6600)
     location = config.get('location', 'MPD')
@@ -64,12 +61,12 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class MpdDevice(MediaPlayerDevice):
-    """ Represents a MPD server. """
+    """Representation of a MPD server."""
 
     # MPD confuses pylint
     # pylint: disable=no-member, abstract-method
-
     def __init__(self, server, port, location, password):
+        """Initialize the MPD device."""
         import mpd
 
         self.server = server
@@ -85,6 +82,7 @@ class MpdDevice(MediaPlayerDevice):
         self.update()
 
     def update(self):
+        """Get the latest data and update the state."""
         import mpd
         try:
             self.status = self.client.status()
@@ -100,12 +98,12 @@ class MpdDevice(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self._name
 
     @property
     def state(self):
-        """ Returns the media state. """
+        """Return the media state."""
         if self.status['state'] == 'play':
             return STATE_PLAYING
         elif self.status['state'] == 'pause':
@@ -115,23 +113,23 @@ class MpdDevice(MediaPlayerDevice):
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         return self.currentsong['id']
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         return MEDIA_TYPE_MUSIC
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         # Time does not exist for streams
         return self.currentsong.get('time')
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         name = self.currentsong.get('name', None)
         title = self.currentsong.get('title', None)
 
@@ -146,61 +144,62 @@ class MpdDevice(MediaPlayerDevice):
 
     @property
     def media_artist(self):
-        """ Artist of current playing media. (Music track only) """
+        """Artist of current playing media (Music track only)."""
         return self.currentsong.get('artist')
 
     @property
     def media_album_name(self):
-        """ Album of current playing media. (Music track only) """
+        """Album of current playing media (Music track only)."""
         return self.currentsong.get('album')
 
     @property
     def volume_level(self):
+        """Return the volume level."""
         return int(self.status['volume'])/100
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_MPD
 
     def turn_off(self):
-        """ Service to send the MPD the command to stop playing. """
+        """Service to send the MPD the command to stop playing."""
         self.client.stop()
 
     def turn_on(self):
-        """ Service to send the MPD the command to start playing. """
+        """Service to send the MPD the command to start playing."""
         self.client.play()
 
     def set_volume_level(self, volume):
-        """ Sets volume """
+        """Set volume of media player."""
         self.client.setvol(int(volume * 100))
 
     def volume_up(self):
-        """ Service to send the MPD the command for volume up. """
+        """Service to send the MPD the command for volume up."""
         current_volume = int(self.status['volume'])
 
         if current_volume <= 100:
             self.client.setvol(current_volume + 5)
 
     def volume_down(self):
-        """ Service to send the MPD the command for volume down. """
+        """Service to send the MPD the command for volume down."""
         current_volume = int(self.status['volume'])
 
         if current_volume >= 0:
             self.client.setvol(current_volume - 5)
 
     def media_play(self):
-        """ Service to send the MPD the command for play/pause. """
+        """Service to send the MPD the command for play/pause."""
         self.client.pause(0)
 
     def media_pause(self):
-        """ Service to send the MPD the command for play/pause. """
+        """Service to send the MPD the command for play/pause."""
         self.client.pause(1)
 
     def media_next_track(self):
-        """ Service to send the MPD the command for next track. """
+        """Service to send the MPD the command for next track."""
         self.client.next()
 
     def media_previous_track(self):
-        """ Service to send the MPD the command for previous track. """
+        """Service to send the MPD the command for previous track."""
         self.client.previous()
diff --git a/homeassistant/components/media_player/plex.py b/homeassistant/components/media_player/plex.py
index 0d68d7e9c30..b472b6c8eba 100644
--- a/homeassistant/components/media_player/plex.py
+++ b/homeassistant/components/media_player/plex.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.plex
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides an interface to the Plex API.
+Support to interface with the Plex API.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.plex/
@@ -35,7 +33,7 @@ SUPPORT_PLEX = SUPPORT_PAUSE | SUPPORT_PREVIOUS_TRACK | SUPPORT_NEXT_TRACK
 
 
 def config_from_file(filename, config=None):
-    """ Small configuration file management function. """
+    """Small configuration file management function."""
     if config:
         # We're writing configuration
         try:
@@ -61,8 +59,7 @@ def config_from_file(filename, config=None):
 
 # pylint: disable=abstract-method
 def setup_platform(hass, config, add_devices_callback, discovery_info=None):
-    """ Sets up the plex platform. """
-
+    """Setup the Plex platform."""
     config = config_from_file(hass.config.path(PLEX_CONFIG_FILE))
     if len(config):
         # Setup a configured PlexServer
@@ -85,7 +82,7 @@ def setup_platform(hass, config, add_devices_callback, discovery_info=None):
 
 # pylint: disable=too-many-branches
 def setup_plexserver(host, token, hass, add_devices_callback):
-    """ Setup a plexserver based on host parameter. """
+    """Setup a plexserver based on host parameter."""
     import plexapi.server
     import plexapi.exceptions
 
@@ -119,7 +116,7 @@ def setup_plexserver(host, token, hass, add_devices_callback):
 
     @util.Throttle(MIN_TIME_BETWEEN_SCANS, MIN_TIME_BETWEEN_FORCED_SCANS)
     def update_devices():
-        """ Updates the devices objects. """
+        """Update the devices objects."""
         try:
             devices = plexserver.clients()
         except plexapi.exceptions.BadRequest:
@@ -145,7 +142,7 @@ def setup_plexserver(host, token, hass, add_devices_callback):
 
     @util.Throttle(MIN_TIME_BETWEEN_SCANS, MIN_TIME_BETWEEN_FORCED_SCANS)
     def update_sessions():
-        """ Updates the sessions objects. """
+        """Update the sessions objects."""
         try:
             sessions = plexserver.sessions()
         except plexapi.exceptions.BadRequest:
@@ -161,7 +158,7 @@ def setup_plexserver(host, token, hass, add_devices_callback):
 
 
 def request_configuration(host, hass, add_devices_callback):
-    """ Request configuration steps from the user. """
+    """Request configuration steps from the user."""
     configurator = get_component('configurator')
 
     # We got an error if this method is called while we are configuring
@@ -172,7 +169,7 @@ def request_configuration(host, hass, add_devices_callback):
         return
 
     def plex_configuration_callback(data):
-        """ Actions to do when our configuration callback is called. """
+        """The actions to do when our configuration callback is called."""
         setup_plexserver(host, data.get('token'), hass, add_devices_callback)
 
     _CONFIGURING[host] = configurator.request_config(
@@ -185,33 +182,34 @@ def request_configuration(host, hass, add_devices_callback):
 
 
 class PlexClient(MediaPlayerDevice):
-    """ Represents a Plex device. """
+    """Representation of a Plex device."""
 
     # pylint: disable=too-many-public-methods, attribute-defined-outside-init
     def __init__(self, device, plex_sessions, update_devices, update_sessions):
+        """Initialize the Plex device."""
         self.plex_sessions = plex_sessions
         self.update_devices = update_devices
         self.update_sessions = update_sessions
         self.set_device(device)
 
     def set_device(self, device):
-        """ Sets the device property. """
+        """Set the device property."""
         self.device = device
 
     @property
     def unique_id(self):
-        """ Returns the id of this plex client """
+        """Return the id of this plex client."""
         return "{}.{}".format(
             self.__class__, self.device.machineIdentifier or self.device.name)
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self.device.name or DEVICE_DEFAULT_NAME
 
     @property
     def session(self):
-        """ Returns the session, if any. """
+        """Return the session, if any."""
         if self.device.machineIdentifier not in self.plex_sessions:
             return None
 
@@ -219,7 +217,7 @@ class PlexClient(MediaPlayerDevice):
 
     @property
     def state(self):
-        """ Returns the state of the device. """
+        """Return the state of the device."""
         if self.session:
             state = self.session.player.state
             if state == 'playing':
@@ -235,18 +233,19 @@ class PlexClient(MediaPlayerDevice):
         return STATE_UNKNOWN
 
     def update(self):
+        """Get the latest details."""
         self.update_devices(no_throttle=True)
         self.update_sessions(no_throttle=True)
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         if self.session is not None:
             return self.session.ratingKey
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         if self.session is None:
             return None
         media_type = self.session.type
@@ -258,61 +257,61 @@ class PlexClient(MediaPlayerDevice):
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         if self.session is not None:
             return self.session.duration
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
+        """Image url of current playing media."""
         if self.session is not None:
             return self.session.thumbUrl
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         # find a string we can use as a title
         if self.session is not None:
             return self.session.title
 
     @property
     def media_season(self):
-        """ Season of curent playing media (TV Show only). """
+        """Season of curent playing media (TV Show only)."""
         from plexapi.video import Show
         if isinstance(self.session, Show):
             return self.session.seasons()[0].index
 
     @property
     def media_series_title(self):
-        """ Series title of current playing media (TV Show only). """
+        """The title of the series of current playing media (TV Show only)."""
         from plexapi.video import Show
         if isinstance(self.session, Show):
             return self.session.grandparentTitle
 
     @property
     def media_episode(self):
-        """ Episode of current playing media (TV Show only). """
+        """Episode of current playing media (TV Show only)."""
         from plexapi.video import Show
         if isinstance(self.session, Show):
             return self.session.index
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_PLEX
 
     def media_play(self):
-        """ media_play media player. """
+        """Send play command."""
         self.device.play()
 
     def media_pause(self):
-        """ media_pause media player. """
+        """Send pause command."""
         self.device.pause()
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self.device.skipNext()
 
     def media_previous_track(self):
-        """ Send previous track command. """
+        """Send previous track command."""
         self.device.skipPrevious()
diff --git a/homeassistant/components/media_player/samsungtv.py b/homeassistant/components/media_player/samsungtv.py
index f7dc7f2a15b..65a243e473a 100644
--- a/homeassistant/components/media_player/samsungtv.py
+++ b/homeassistant/components/media_player/samsungtv.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.denon
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides an interface to Samsung TV with a Laninterface.
+Support for interface with an Samsung TV.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.samsungtv/
@@ -31,8 +29,7 @@ SUPPORT_SAMSUNGTV = SUPPORT_PAUSE | SUPPORT_VOLUME_STEP | \
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the Samsung TV platform. """
-
+    """Setup the Samsung TV platform."""
     # Validate that all required config options are given
     if not validate_config({DOMAIN: config}, {DOMAIN: [CONF_HOST]}, _LOGGER):
         return False
@@ -55,10 +52,11 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 # pylint: disable=abstract-method
 class SamsungTVDevice(MediaPlayerDevice):
-    """ Represents a Samsung TV. """
+    """Representation of a Samsung TV."""
 
     # pylint: disable=too-many-public-methods
     def __init__(self, name, config):
+        """Initialize the samsung device."""
         from samsungctl import Remote
         # Save a reference to the imported class
         self._remote_class = Remote
@@ -72,12 +70,12 @@ class SamsungTVDevice(MediaPlayerDevice):
         self._config = config
 
     def update(self):
+        """Retrieve the latest data."""
         # Send an empty key to see if we are still connected
         return self.send_key('KEY_POWER')
 
     def get_remote(self):
-        """ Creates or Returns a remote control instance """
-
+        """Create or return a remote control instance."""
         if self._remote is None:
             # We need to create a new instance to reconnect.
             self._remote = self._remote_class(self._config)
@@ -85,7 +83,7 @@ class SamsungTVDevice(MediaPlayerDevice):
         return self._remote
 
     def send_key(self, key):
-        """ Sends a key to the tv and handles exceptions """
+        """Send a key to the tv and handles exceptions."""
         try:
             self.get_remote().control(key)
             self._state = STATE_ON
@@ -106,62 +104,65 @@ class SamsungTVDevice(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self._name
 
     @property
     def state(self):
+        """Return the state of the device."""
         return self._state
 
     @property
     def is_volume_muted(self):
-        """ Boolean if volume is currently muted. """
+        """Boolean if volume is currently muted."""
         return self._muted
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_SAMSUNGTV
 
     def turn_off(self):
-        """ turn_off media player. """
+        """Turn off media player."""
         self.send_key("KEY_POWEROFF")
 
     def volume_up(self):
-        """ volume_up media player. """
+        """Volume up the media player."""
         self.send_key("KEY_VOLUP")
 
     def volume_down(self):
-        """ volume_down media player. """
+        """Volume down media player."""
         self.send_key("KEY_VOLDOWN")
 
     def mute_volume(self, mute):
+        """Send mute command."""
         self.send_key("KEY_MUTE")
 
     def media_play_pause(self):
-        """ Simulate play pause media player. """
+        """Simulate play pause media player."""
         if self._playing:
             self.media_pause()
         else:
             self.media_play()
 
     def media_play(self):
-        """ media_play media player. """
+        """Send play command."""
         self._playing = True
         self.send_key("KEY_PLAY")
 
     def media_pause(self):
-        """ media_pause media player. """
+        """Send media pause command to media player."""
         self._playing = False
         self.send_key("KEY_PAUSE")
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self.send_key("KEY_FF")
 
     def media_previous_track(self):
+        """Send the previous track command."""
         self.send_key("KEY_REWIND")
 
     def turn_on(self):
-        """ turn the media player on. """
+        """Turn the media player on."""
         self.send_key("KEY_POWERON")
diff --git a/homeassistant/components/media_player/snapcast.py b/homeassistant/components/media_player/snapcast.py
index 5c8bd24a79d..6bdbe9c6183 100644
--- a/homeassistant/components/media_player/snapcast.py
+++ b/homeassistant/components/media_player/snapcast.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.snapcast
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides functionality to interact with Snapcast clients.
+Support for interacting with Snapcast clients.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.snapcast/
@@ -22,7 +20,7 @@ _LOGGER = logging.getLogger(__name__)
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the Snapcast platform. """
+    """Setup the Snapcast platform."""
     import snapcast.control
     host = config.get('host')
     port = config.get('port', snapcast.control.CONTROL_PORT)
@@ -39,44 +37,44 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class SnapcastDevice(MediaPlayerDevice):
-    """ Represents a Snapcast client device. """
+    """Representation of a Snapcast client device."""
 
     # pylint: disable=abstract-method
-
     def __init__(self, client):
+        """Initialize the Snapcast device."""
         self._client = client
 
     @property
     def name(self):
-        """ Device name. """
+        """Return the name of the device."""
         return self._client.identifier
 
     @property
     def volume_level(self):
-        """ Volume level. """
+        """Return the volume level."""
         return self._client.volume / 100
 
     @property
     def is_volume_muted(self):
-        """ Volume muted. """
+        """Volume muted."""
         return self._client.muted
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_SNAPCAST
 
     @property
     def state(self):
-        """ State of the player. """
+        """Return the state of the player."""
         if self._client.connected:
             return STATE_ON
         return STATE_OFF
 
     def mute_volume(self, mute):
-        """ Mute status. """
+        """Send the mute command."""
         self._client.muted = mute
 
     def set_volume_level(self, volume):
-        """ Volume level. """
+        """Set the volume level."""
         self._client.volume = round(volume * 100)
diff --git a/homeassistant/components/media_player/sonos.py b/homeassistant/components/media_player/sonos.py
index 70b7d911cca..129bb42a737 100644
--- a/homeassistant/components/media_player/sonos.py
+++ b/homeassistant/components/media_player/sonos.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.sonos
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides an interface to Sonos players (via SoCo)
+Support to interface with Sonos players (via SoCo).
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.sonos/
@@ -34,7 +32,7 @@ SUPPORT_SONOS = SUPPORT_PAUSE | SUPPORT_VOLUME_SET | SUPPORT_VOLUME_MUTE |\
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the Sonos platform. """
+    """Setup the Sonos platform."""
     import soco
     import socket
 
@@ -67,15 +65,14 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 def only_if_coordinator(func):
-    """
-    If used as decorator, avoid calling the decorated method if
-    player is not a coordinator.
-    If not, a grouped speaker (not in coordinator role)
-    will throw soco.exceptions.SoCoSlaveException
-    """
+    """Decorator for coordinator.
 
+    If used as decorator, avoid calling the decorated method if player is not
+    a coordinator. If not, a grouped speaker (not in coordinator role) will
+    throw soco.exceptions.SoCoSlaveException
+    """
     def wrapper(*args, **kwargs):
-        """ Decorator wrapper """
+        """Decorator wrapper."""
         if args[0].is_coordinator:
             return func(*args, **kwargs)
         else:
@@ -89,10 +86,11 @@ def only_if_coordinator(func):
 # pylint: disable=too-many-instance-attributes, too-many-public-methods
 # pylint: disable=abstract-method
 class SonosDevice(MediaPlayerDevice):
-    """ Represents a Sonos device. """
+    """Representation of a Sonos device."""
 
     # pylint: disable=too-many-arguments
     def __init__(self, hass, player):
+        """Initialize the Sonos device."""
         self.hass = hass
         super(SonosDevice, self).__init__()
         self._player = player
@@ -100,25 +98,26 @@ class SonosDevice(MediaPlayerDevice):
 
     @property
     def should_poll(self):
+        """No polling needed."""
         return True
 
     def update_sonos(self, now):
-        """ Updates state, called by track_utc_time_change. """
+        """Update state, called by track_utc_time_change."""
         self.update_ha_state(True)
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self._name
 
     @property
     def unique_id(self):
-        """ Returns a unique id. """
+        """Return a unique ID."""
         return "{}.{}".format(self.__class__, self._player.uid)
 
     @property
     def state(self):
-        """ Returns the state of the device. """
+        """Return the state of the device."""
         if self._status == 'PAUSED_PLAYBACK':
             return STATE_PAUSED
         if self._status == 'PLAYING':
@@ -129,11 +128,11 @@ class SonosDevice(MediaPlayerDevice):
 
     @property
     def is_coordinator(self):
-        """ Returns true if player is a coordinator """
+        """Return true if player is a coordinator."""
         return self._player.is_coordinator
 
     def update(self):
-        """ Retrieve latest state. """
+        """Retrieve latest state."""
         self._name = self._player.get_speaker_info()['zone_name'].replace(
             ' (R)', '').replace(' (L)', '')
         self._status = self._player.get_current_transport_info().get(
@@ -142,26 +141,27 @@ class SonosDevice(MediaPlayerDevice):
 
     @property
     def volume_level(self):
-        """ Volume level of the media player (0..1). """
+        """Volume level of the media player (0..1)."""
         return self._player.volume / 100.0
 
     @property
     def is_volume_muted(self):
+        """Return true if volume is muted."""
         return self._player.mute
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         return self._trackinfo.get('title', None)
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         return MEDIA_TYPE_MUSIC
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         dur = self._trackinfo.get('duration', '0:00')
 
         # If the speaker is playing from the "line-in" source, getting
@@ -175,13 +175,13 @@ class SonosDevice(MediaPlayerDevice):
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
+        """Image url of current playing media."""
         if 'album_art' in self._trackinfo:
             return self._trackinfo['album_art']
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         if 'artist' in self._trackinfo and 'title' in self._trackinfo:
             return '{artist} - {title}'.format(
                 artist=self._trackinfo['artist'],
@@ -192,60 +192,60 @@ class SonosDevice(MediaPlayerDevice):
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_SONOS
 
     @only_if_coordinator
     def turn_off(self):
-        """ Turn off media player. """
+        """Turn off media player."""
         self._player.pause()
 
     @only_if_coordinator
     def volume_up(self):
-        """ Volume up media player. """
+        """Volume up media player."""
         self._player.volume += 1
 
     @only_if_coordinator
     def volume_down(self):
-        """ Volume down media player. """
+        """Volume down media player."""
         self._player.volume -= 1
 
     @only_if_coordinator
     def set_volume_level(self, volume):
-        """ Set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         self._player.volume = str(int(volume * 100))
 
     @only_if_coordinator
     def mute_volume(self, mute):
-        """ Mute (true) or unmute (false) media player. """
+        """Mute (true) or unmute (false) media player."""
         self._player.mute = mute
 
     @only_if_coordinator
     def media_play(self):
-        """ Send paly command. """
+        """Send paly command."""
         self._player.play()
 
     @only_if_coordinator
     def media_pause(self):
-        """ Send pause command. """
+        """Send pause command."""
         self._player.pause()
 
     @only_if_coordinator
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self._player.next()
 
     @only_if_coordinator
     def media_previous_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self._player.previous()
 
     @only_if_coordinator
     def media_seek(self, position):
-        """ Send seek command. """
+        """Send seek command."""
         self._player.seek(str(datetime.timedelta(seconds=int(position))))
 
     @only_if_coordinator
     def turn_on(self):
-        """ Turn the media player on. """
+        """Turn the media player on."""
         self._player.play()
diff --git a/homeassistant/components/media_player/squeezebox.py b/homeassistant/components/media_player/squeezebox.py
index 457e1bc539a..f22d9f20f08 100644
--- a/homeassistant/components/media_player/squeezebox.py
+++ b/homeassistant/components/media_player/squeezebox.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.squeezebox
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provides an interface to the Logitech SqueezeBox API
+Support for interfacing to the Logitech SqueezeBox API.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.squeezebox/
@@ -26,7 +24,7 @@ SUPPORT_SQUEEZEBOX = SUPPORT_PAUSE | SUPPORT_VOLUME_SET | \
 
 
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ Sets up the squeezebox platform. """
+    """Setup the squeezebox platform."""
     if not config.get(CONF_HOST):
         _LOGGER.error(
             "Missing required configuration items in %s: %s",
@@ -49,9 +47,10 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 class LogitechMediaServer(object):
-    """ Represents a Logitech media server. """
+    """Representation of a Logitech media server."""
 
     def __init__(self, host, port, username, password):
+        """Initialize the Logitech device."""
         self.host = host
         self.port = port
         self._username = username
@@ -60,7 +59,7 @@ class LogitechMediaServer(object):
         self.init_success = True if self.http_port else False
 
     def _get_http_port(self):
-        """ Get http port from media server, it is used to get cover art. """
+        """Get http port from media server, it is used to get cover art."""
         http_port = None
         try:
             http_port = self.query('pref', 'httpport', '?')
@@ -80,7 +79,7 @@ class LogitechMediaServer(object):
             return
 
     def create_players(self):
-        """ Create a list of SqueezeBoxDevices connected to the LMS. """
+        """Create a list of SqueezeBoxDevices connected to the LMS."""
         players = []
         count = self.query('player', 'count', '?')
         for index in range(0, int(count)):
@@ -90,7 +89,7 @@ class LogitechMediaServer(object):
         return players
 
     def query(self, *parameters):
-        """ Send request and await response from server. """
+        """Send request and await response from server."""
         telnet = telnetlib.Telnet(self.host, self.port)
         if self._username and self._password:
             telnet.write('login {username} {password}\n'.format(
@@ -107,7 +106,7 @@ class LogitechMediaServer(object):
         return urllib.parse.unquote(response)
 
     def get_player_status(self, player):
-        """ Get ithe status of a player. """
+        """Get ithe status of a player."""
         #   (title) : Song title
         # Requested Information
         # a (artist): Artist name 'artist'
@@ -133,10 +132,11 @@ class LogitechMediaServer(object):
 # pylint: disable=too-many-instance-attributes
 # pylint: disable=too-many-public-methods
 class SqueezeBoxDevice(MediaPlayerDevice):
-    """ Represents a SqueezeBox device. """
+    """Representation of a SqueezeBox device."""
 
     # pylint: disable=too-many-arguments, abstract-method
     def __init__(self, lms, player_id):
+        """Initialize the SqeezeBox device."""
         super(SqueezeBoxDevice, self).__init__()
         self._lms = lms
         self._id = player_id
@@ -145,12 +145,12 @@ class SqueezeBoxDevice(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ Returns the name of the device. """
+        """Return the name of the device."""
         return self._name
 
     @property
     def state(self):
-        """ Returns the state of the device. """
+        """Return the state of the device."""
         if 'power' in self._status and self._status['power'] == '0':
             return STATE_OFF
         if 'mode' in self._status:
@@ -163,40 +163,41 @@ class SqueezeBoxDevice(MediaPlayerDevice):
         return STATE_UNKNOWN
 
     def update(self):
-        """ Retrieve latest state. """
+        """Retrieve latest state."""
         self._status = self._lms.get_player_status(self._id)
 
     @property
     def volume_level(self):
-        """ Volume level of the media player (0..1). """
+        """Volume level of the media player (0..1)."""
         if 'mixer volume' in self._status:
             return int(float(self._status['mixer volume'])) / 100.0
 
     @property
     def is_volume_muted(self):
+        """Return true if volume is muted."""
         if 'mixer volume' in self._status:
             return self._status['mixer volume'].startswith('-')
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         if 'current_title' in self._status:
             return self._status['current_title']
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         return MEDIA_TYPE_MUSIC
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         if 'duration' in self._status:
             return int(float(self._status['duration']))
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
+        """Image url of current playing media."""
         if 'artwork_url' in self._status:
             media_url = self._status['artwork_url']
         elif 'id' in self._status:
@@ -214,7 +215,7 @@ class SqueezeBoxDevice(MediaPlayerDevice):
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         if 'artist' in self._status and 'title' in self._status:
             return '{artist} - {title}'.format(
                 artist=self._status['artist'],
@@ -225,67 +226,67 @@ class SqueezeBoxDevice(MediaPlayerDevice):
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         return SUPPORT_SQUEEZEBOX
 
     def turn_off(self):
-        """ turn_off media player. """
+        """Turn off media player."""
         self._lms.query(self._id, 'power', '0')
         self.update_ha_state()
 
     def volume_up(self):
-        """ volume_up media player. """
+        """Volume up media player."""
         self._lms.query(self._id, 'mixer', 'volume', '+5')
         self.update_ha_state()
 
     def volume_down(self):
-        """ volume_down media player. """
+        """Volume down media player."""
         self._lms.query(self._id, 'mixer', 'volume', '-5')
         self.update_ha_state()
 
     def set_volume_level(self, volume):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         volume_percent = str(int(volume*100))
         self._lms.query(self._id, 'mixer', 'volume', volume_percent)
         self.update_ha_state()
 
     def mute_volume(self, mute):
-        """ mute (true) or unmute (false) media player. """
+        """Mute (true) or unmute (false) media player."""
         mute_numeric = '1' if mute else '0'
         self._lms.query(self._id, 'mixer', 'muting', mute_numeric)
         self.update_ha_state()
 
     def media_play_pause(self):
-        """ media_play_pause media player. """
+        """Send pause command to media player."""
         self._lms.query(self._id, 'pause')
         self.update_ha_state()
 
     def media_play(self):
-        """ media_play media player. """
+        """Send play command to media player."""
         self._lms.query(self._id, 'play')
         self.update_ha_state()
 
     def media_pause(self):
-        """ media_pause media player. """
+        """Send pause command to media player."""
         self._lms.query(self._id, 'pause', '1')
         self.update_ha_state()
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self._lms.query(self._id, 'playlist', 'index', '+1')
         self.update_ha_state()
 
     def media_previous_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self._lms.query(self._id, 'playlist', 'index', '-1')
         self.update_ha_state()
 
     def media_seek(self, position):
-        """ Send seek command. """
+        """Send seek command."""
         self._lms.query(self._id, 'time', position)
         self.update_ha_state()
 
     def turn_on(self):
-        """ turn the media player on. """
+        """Turn the media player on."""
         self._lms.query(self._id, 'power', '1')
         self.update_ha_state()
diff --git a/homeassistant/components/media_player/universal.py b/homeassistant/components/media_player/universal.py
index 2bc4a8506f6..8c981c42e0d 100644
--- a/homeassistant/components/media_player/universal.py
+++ b/homeassistant/components/media_player/universal.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.media_player.universal
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Combines multiple media players into one for a universal controller.
+Combination of multiple media players into one for a universal controller.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/media_player.universal/
@@ -47,7 +45,7 @@ _LOGGER = logging.getLogger(__name__)
 
 # pylint: disable=unused-argument
 def setup_platform(hass, config, add_devices, discovery_info=None):
-    """ sets up the universal media players """
+    """Setup the universal media players."""
     if not validate_config(config):
         return
 
@@ -61,10 +59,10 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
 
 
 def validate_config(config):
-    """ validate universal media player configuration """
+    """Validate universal media player configuration."""
     del config[CONF_PLATFORM]
 
-    # validate name
+    # Validate name
     if CONF_NAME not in config:
         _LOGGER.error('Universal Media Player configuration requires name')
         return False
@@ -87,7 +85,7 @@ def validate_config(config):
 
 
 def validate_children(config):
-    """ validate children """
+    """Validate children."""
     if CONF_CHILDREN not in config:
         _LOGGER.info(
             'No children under Universal Media Player (%s)', config[CONF_NAME])
@@ -101,7 +99,7 @@ def validate_children(config):
 
 
 def validate_commands(config):
-    """ validate commands """
+    """Validate commands."""
     if CONF_COMMANDS not in config:
         config[CONF_COMMANDS] = {}
     elif not isinstance(config[CONF_COMMANDS], dict):
@@ -113,7 +111,7 @@ def validate_commands(config):
 
 
 def validate_attributes(config):
-    """ validate attributes """
+    """Validate attributes."""
     if CONF_ATTRS not in config:
         config[CONF_ATTRS] = {}
     elif not isinstance(config[CONF_ATTRS], dict):
@@ -131,10 +129,11 @@ def validate_attributes(config):
 
 
 class UniversalMediaPlayer(MediaPlayerDevice):
-    """ Represents a universal media player in HA """
-    # pylint: disable=too-many-public-methods
+    """Representation of an universal media player."""
 
+    # pylint: disable=too-many-public-methods
     def __init__(self, hass, name, children, commands, attributes):
+        """Initialize the Universal media device."""
         # pylint: disable=too-many-arguments
         self.hass = hass
         self._name = name
@@ -144,7 +143,7 @@ class UniversalMediaPlayer(MediaPlayerDevice):
         self._child_state = None
 
         def on_dependency_update(*_):
-            """ update ha state when dependencies update """
+            """Update ha state when dependencies update."""
             self.update_ha_state(True)
 
         depend = copy(children)
@@ -154,7 +153,7 @@ class UniversalMediaPlayer(MediaPlayerDevice):
         track_state_change(hass, depend, on_dependency_update)
 
     def _entity_lkp(self, entity_id, state_attr=None):
-        """ Looks up an entity state from hass """
+        """Look up an entity state."""
         state_obj = self.hass.states.get(entity_id)
 
         if state_obj is None:
@@ -165,7 +164,7 @@ class UniversalMediaPlayer(MediaPlayerDevice):
         return state_obj.state
 
     def _override_or_child_attr(self, attr_name):
-        """ returns either the override or the active child for attr_name """
+        """Return either the override or the active child for attr_name."""
         if attr_name in self._attrs:
             return self._entity_lkp(self._attrs[attr_name][0],
                                     self._attrs[attr_name][1])
@@ -173,13 +172,13 @@ class UniversalMediaPlayer(MediaPlayerDevice):
         return self._child_attr(attr_name)
 
     def _child_attr(self, attr_name):
-        """ returns the active child's attr """
+        """Return the active child's attributes."""
         active_child = self._child_state
         return active_child.attributes.get(attr_name) if active_child else None
 
     def _call_service(self, service_name, service_data=None,
                       allow_override=False):
-        """ calls either a specified or active child's service """
+        """Call either a specified or active child's service."""
         if allow_override and service_name in self._cmds:
             call_from_config(
                 self.hass, self._cmds[service_name], blocking=True)
@@ -196,12 +195,12 @@ class UniversalMediaPlayer(MediaPlayerDevice):
 
     @property
     def should_poll(self):
-        """ Indicates whether HA should poll for updates """
+        """No polling needed."""
         return False
 
     @property
     def master_state(self):
-        """ gets the master state from entity or none """
+        """Get the master state from entity or none."""
         if CONF_STATE in self._attrs:
             master_state = self._entity_lkp(self._attrs[CONF_STATE][0],
                                             self._attrs[CONF_STATE][1])
@@ -211,17 +210,16 @@ class UniversalMediaPlayer(MediaPlayerDevice):
 
     @property
     def name(self):
-        """ name of universal player """
+        """Return the name of universal player."""
         return self._name
 
     @property
     def state(self):
-        """
-        Current state of media player
+        """Current state of media player.
 
         Off if master state is off
-        ELSE Status of first active child
-        ELSE master state or off
+        else Status of first active child
+        else master state or off
         """
         master_state = self.master_state  # avoid multiple lookups
         if master_state == STATE_OFF:
@@ -235,98 +233,98 @@ class UniversalMediaPlayer(MediaPlayerDevice):
 
     @property
     def volume_level(self):
-        """ Volume level of entity specified in attributes or active child """
+        """Volume level of entity specified in attributes or active child."""
         return self._child_attr(ATTR_MEDIA_VOLUME_LEVEL)
 
     @property
     def is_volume_muted(self):
-        """ boolean if volume is muted """
+        """Boolean if volume is muted."""
         return self._override_or_child_attr(ATTR_MEDIA_VOLUME_MUTED) \
             in [True, STATE_ON]
 
     @property
     def media_content_id(self):
-        """ Content ID of current playing media. """
+        """Content ID of current playing media."""
         return self._child_attr(ATTR_MEDIA_CONTENT_ID)
 
     @property
     def media_content_type(self):
-        """ Content type of current playing media. """
+        """Content type of current playing media."""
         return self._child_attr(ATTR_MEDIA_CONTENT_TYPE)
 
     @property
     def media_duration(self):
-        """ Duration of current playing media in seconds. """
+        """Duration of current playing media in seconds."""
         return self._child_attr(ATTR_MEDIA_DURATION)
 
     @property
     def media_image_url(self):
-        """ Image url of current playing media. """
+        """Image url of current playing media."""
         return self._child_attr(ATTR_ENTITY_PICTURE)
 
     @property
     def media_title(self):
-        """ Title of current playing media. """
+        """Title of current playing media."""
         return self._child_attr(ATTR_MEDIA_TITLE)
 
     @property
     def media_artist(self):
-        """ Artist of current playing media. (Music track only) """
+        """Artist of current playing media (Music track only)."""
         return self._child_attr(ATTR_MEDIA_ARTIST)
 
     @property
     def media_album_name(self):
-        """ Album name of current playing media. (Music track only) """
+        """Album name of current playing media (Music track only)."""
         return self._child_attr(ATTR_MEDIA_ALBUM_NAME)
 
     @property
     def media_album_artist(self):
-        """ Album arist of current playing media. (Music track only) """
+        """Album artist of current playing media (Music track only)."""
         return self._child_attr(ATTR_MEDIA_ALBUM_ARTIST)
 
     @property
     def media_track(self):
-        """ Track number of current playing media. (Music track only) """
+        """Track number of current playing media (Music track only)."""
         return self._child_attr(ATTR_MEDIA_TRACK)
 
     @property
     def media_series_title(self):
-        """ Series title of current playing media. (TV Show only)"""
+        """The title of the series of current playing media (TV Show only)."""
         return self._child_attr(ATTR_MEDIA_SERIES_TITLE)
 
     @property
     def media_season(self):
-        """ Season of current playing media. (TV Show only) """
+        """Season of current playing media (TV Show only)."""
         return self._child_attr(ATTR_MEDIA_SEASON)
 
     @property
     def media_episode(self):
-        """ Episode of current playing media. (TV Show only) """
+        """Episode of current playing media (TV Show only)."""
         return self._child_attr(ATTR_MEDIA_EPISODE)
 
     @property
     def media_channel(self):
-        """ Channel currently playing. """
+        """Channel currently playing."""
         return self._child_attr(ATTR_MEDIA_CHANNEL)
 
     @property
     def media_playlist(self):
-        """ Title of Playlist currently playing. """
+        """Title of Playlist currently playing."""
         return self._child_attr(ATTR_MEDIA_PLAYLIST)
 
     @property
     def app_id(self):
-        """  ID of the current running app. """
+        """ID of the current running app."""
         return self._child_attr(ATTR_APP_ID)
 
     @property
     def app_name(self):
-        """  Name of the current running app. """
+        """Name of the current running app."""
         return self._child_attr(ATTR_APP_NAME)
 
     @property
     def supported_media_commands(self):
-        """ Flags of media commands that are supported. """
+        """Flag of media commands that are supported."""
         flags = self._child_attr(ATTR_SUPPORTED_MEDIA_COMMANDS) or 0
 
         if SERVICE_TURN_ON in self._cmds:
@@ -347,69 +345,69 @@ class UniversalMediaPlayer(MediaPlayerDevice):
 
     @property
     def device_state_attributes(self):
-        """ Extra attributes a device wants to expose. """
+        """Extra attributes a device wants to expose."""
         active_child = self._child_state
         return {ATTR_ACTIVE_CHILD: active_child.entity_id} \
             if active_child else {}
 
     def turn_on(self):
-        """ turn the media player on. """
+        """Turn the media player on."""
         self._call_service(SERVICE_TURN_ON, allow_override=True)
 
     def turn_off(self):
-        """ turn the media player off. """
+        """Turn the media player off."""
         self._call_service(SERVICE_TURN_OFF, allow_override=True)
 
     def mute_volume(self, is_volume_muted):
-        """ mute the volume. """
+        """Mute the volume."""
         data = {ATTR_MEDIA_VOLUME_MUTED: is_volume_muted}
         self._call_service(SERVICE_VOLUME_MUTE, data, allow_override=True)
 
     def set_volume_level(self, volume_level):
-        """ set volume level, range 0..1. """
+        """Set volume level, range 0..1."""
         data = {ATTR_MEDIA_VOLUME_LEVEL: volume_level}
         self._call_service(SERVICE_VOLUME_SET, data)
 
     def media_play(self):
-        """ Send play commmand. """
+        """Send play commmand."""
         self._call_service(SERVICE_MEDIA_PLAY)
 
     def media_pause(self):
-        """ Send pause command. """
+        """Send pause command."""
         self._call_service(SERVICE_MEDIA_PAUSE)
 
     def media_previous_track(self):
-        """ Send previous track command. """
+        """Send previous track command."""
         self._call_service(SERVICE_MEDIA_PREVIOUS_TRACK)
 
     def media_next_track(self):
-        """ Send next track command. """
+        """Send next track command."""
         self._call_service(SERVICE_MEDIA_NEXT_TRACK)
 
     def media_seek(self, position):
-        """ Send seek command. """
+        """Send seek command."""
         data = {ATTR_MEDIA_SEEK_POSITION: position}
         self._call_service(SERVICE_MEDIA_SEEK, data)
 
     def play_media(self, media_type, media_id):
-        """ Plays a piece of media. """
+        """Play a piece of media."""
         data = {'media_type': media_type, 'media_id': media_id}
         self._call_service(SERVICE_PLAY_MEDIA, data)
 
     def volume_up(self):
-        """ volume_up media player. """
+        """Volume up media player."""
         self._call_service(SERVICE_VOLUME_UP, allow_override=True)
 
     def volume_down(self):
-        """ volume_down media player. """
+        """Volume down media player."""
         self._call_service(SERVICE_VOLUME_DOWN, allow_override=True)
 
     def media_play_pause(self):
-        """ media_play_pause media player. """
+        """Send play/pause command media player."""
         self._call_service(SERVICE_MEDIA_PLAY_PAUSE)
 
     def update(self):
-        """ event to trigger a state update in HA """
+        """Event to trigger a state update."""
         for child_name in self._children:
             child_state = self.hass.states.get(child_name)
             if child_state and child_state.state not in OFF_STATES: