Use core constants for file integration (#46171)

homeassistant/components/file/sensor.py

@@ -5,14 +5,17 @@ import os
 import voluptuous as vol
 
 from homeassistant.components.sensor import PLATFORM_SCHEMA
-from homeassistant.const import CONF_NAME, CONF_UNIT_OF_MEASUREMENT, CONF_VALUE_TEMPLATE
+from homeassistant.const import (
+    CONF_FILE_PATH,
+    CONF_NAME,
+    CONF_UNIT_OF_MEASUREMENT,
+    CONF_VALUE_TEMPLATE,
+)
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import Entity
 
 _LOGGER = logging.getLogger(__name__)
 
-CONF_FILE_PATH = "file_path"
-
 DEFAULT_NAME = "File"
 
 ICON = "mdi:file"