old_contents: """
  homeassistant.components.sensor.demo
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  Demo platform that has a couple of fake sensors.
  """
  from homeassistant.helpers.entity import Entity
  from homeassistant.const import TEMP_CELCIUS, ATTR_BATTERY_LEVEL
  
  
  # pylint: disable=unused-argument
  def setup_platform(hass, config, add_devices, discovery_info=None):
      """ Sets up the Demo sensors. """
      add_devices([
          DemoSensor('Outside Temperature', 15.6, TEMP_CELCIUS, 12),
          DemoSensor('Outside Humidity', 54, '%', None),
          DemoSensor('Alarm back', 'Armed', None, None),
      ])
  
  
  class DemoSensor(Entity):
      """ A Demo sensor. """
  
      def __init__(self, name, state, unit_of_measurement, battery):
          self._name = name
          self._state = state
          self._unit_of_measurement = unit_of_measurement
          self._battery = battery
  
      @property
      def should_poll(self):
          """ No polling needed for a demo sensor. """
          return False
  
      @property
      def name(self):
          """ Returns the name of the device. """
          return self._name
  
      @property
      def state(self):
          """ Returns the state of the device. """
          return self._state
  
      @property
      def unit_of_measurement(self):
          """ Unit this state is expressed in. """
          return self._unit_of_measurement
  
      @property
      def state_attributes(self):
          """ Returns the state attributes. """
          if self._battery:
              return {
                  ATTR_BATTERY_LEVEL: self._battery,
              }
  
new_contents: """
  homeassistant.components.sensor.demo
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  Demo platform that has a couple of fake sensors.
  """
  from homeassistant.helpers.entity import Entity
  from homeassistant.const import TEMP_CELCIUS, ATTR_BATTERY_LEVEL
  
  
  # pylint: disable=unused-argument
  def setup_platform(hass, config, add_devices, discovery_info=None):
      """ Sets up the Demo sensors. """
      add_devices([
          DemoSensor('Outside Temperature', 15.6, TEMP_CELCIUS, 12),
          DemoSensor('Outside Humidity', 54, '%', None),
      ])
  
  
  class DemoSensor(Entity):
      """ A Demo sensor. """
  
      def __init__(self, name, state, unit_of_measurement, battery):
          self._name = name
          self._state = state
          self._unit_of_measurement = unit_of_measurement
          self._battery = battery
  
      @property
      def should_poll(self):
          """ No polling needed for a demo sensor. """
          return False
  
      @property
      def name(self):
          """ Returns the name of the device. """
          return self._name
  
      @property
      def state(self):
          """ Returns the state of the device. """
          return self._state
  
      @property
      def unit_of_measurement(self):
          """ Unit this state is expressed in. """
          return self._unit_of_measurement
  
      @property
      def state_attributes(self):
          """ Returns the state attributes. """
          if self._battery:
              return {
                  ATTR_BATTERY_LEVEL: self._battery,
              }
  
subject: Remove alarm sensor from demo platform