Add and use light lux constant in entire code base (#40171)

homeassistant/components/homekit_controller/sensor.py

@@ -7,6 +7,7 @@ from homeassistant.const import (
     DEVICE_CLASS_HUMIDITY,
     DEVICE_CLASS_ILLUMINANCE,
     DEVICE_CLASS_TEMPERATURE,
+    LIGHT_LUX,
     PERCENTAGE,
     TEMP_CELSIUS,
 )
@@ -19,8 +20,6 @@ TEMP_C_ICON = "mdi:thermometer"
 BRIGHTNESS_ICON = "mdi:brightness-6"
 CO2_ICON = "mdi:molecule-co2"
 
-UNIT_LUX = "lux"
-
 
 class HomeKitHumiditySensor(HomeKitEntity):
     """Representation of a Homekit humidity sensor."""
@@ -113,7 +112,7 @@ class HomeKitLightSensor(HomeKitEntity):
     @property
     def unit_of_measurement(self):
         """Return units for the sensor."""
-        return UNIT_LUX
+        return LIGHT_LUX
 
     @property
     def state(self):