old_contents: """Platform to retrieve uptime for Home Assistant."""
  from __future__ import annotations
  
  import voluptuous as vol
  
  from homeassistant.components.sensor import PLATFORM_SCHEMA, SensorEntity
  from homeassistant.const import (
      CONF_NAME,
      CONF_UNIT_OF_MEASUREMENT,
      DEVICE_CLASS_TIMESTAMP,
  )
  from homeassistant.core import HomeAssistant
  import homeassistant.helpers.config_validation as cv
  from homeassistant.helpers.entity_platform import AddEntitiesCallback
  from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
  import homeassistant.util.dt as dt_util
  
  DEFAULT_NAME = "Uptime"
  
  PLATFORM_SCHEMA = vol.All(
      cv.deprecated(CONF_UNIT_OF_MEASUREMENT),
      PLATFORM_SCHEMA.extend(
          {
              vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
              vol.Optional(CONF_UNIT_OF_MEASUREMENT, default="days"): vol.All(
                  cv.string, vol.In(["minutes", "hours", "days", "seconds"])
              ),
          }
      ),
  )
  
  
  async def async_setup_platform(
      hass: HomeAssistant,
      config: ConfigType,
      async_add_entities: AddEntitiesCallback,
      discovery_info: DiscoveryInfoType | None = None,
  ) -> None:
      """Set up the uptime sensor platform."""
      name = config[CONF_NAME]
  
      async_add_entities([UptimeSensor(name)], True)
  
  
  class UptimeSensor(SensorEntity):
      """Representation of an uptime sensor."""
  
      def __init__(self, name: str) -> None:
          """Initialize the uptime sensor."""
          self._attr_name: str = name
          self._attr_device_class: str = DEVICE_CLASS_TIMESTAMP
          self._attr_should_poll: bool = False
          self._attr_native_value = dt_util.utcnow()
  
new_contents: """Platform to retrieve uptime for Home Assistant."""
  from __future__ import annotations
  
  import voluptuous as vol
  
  from homeassistant.components.sensor import (
      PLATFORM_SCHEMA,
      SensorDeviceClass,
      SensorEntity,
  )
  from homeassistant.const import CONF_NAME, CONF_UNIT_OF_MEASUREMENT
  from homeassistant.core import HomeAssistant
  import homeassistant.helpers.config_validation as cv
  from homeassistant.helpers.entity_platform import AddEntitiesCallback
  from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
  import homeassistant.util.dt as dt_util
  
  DEFAULT_NAME = "Uptime"
  
  PLATFORM_SCHEMA = vol.All(
      cv.deprecated(CONF_UNIT_OF_MEASUREMENT),
      PLATFORM_SCHEMA.extend(
          {
              vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
              vol.Optional(CONF_UNIT_OF_MEASUREMENT, default="days"): vol.All(
                  cv.string, vol.In(["minutes", "hours", "days", "seconds"])
              ),
          }
      ),
  )
  
  
  async def async_setup_platform(
      hass: HomeAssistant,
      config: ConfigType,
      async_add_entities: AddEntitiesCallback,
      discovery_info: DiscoveryInfoType | None = None,
  ) -> None:
      """Set up the uptime sensor platform."""
      name = config[CONF_NAME]
  
      async_add_entities([UptimeSensor(name)], True)
  
  
  class UptimeSensor(SensorEntity):
      """Representation of an uptime sensor."""
  
      def __init__(self, name: str) -> None:
          """Initialize the uptime sensor."""
          self._attr_name: str = name
          self._attr_device_class = SensorDeviceClass.TIMESTAMP
          self._attr_should_poll: bool = False
          self._attr_native_value = dt_util.utcnow()
  
subject: Use enums in uptime (#62032)