old_contents: """
  homeassistant.components.automation.event
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
  Offers event listening automation rules.
  """
  import logging
  
  CONF_EVENT_TYPE = "event_type"
  CONF_EVENT_DATA = "event_data"
  
  _LOGGER = logging.getLogger(__name__)
  
  
  def trigger(hass, config, action):
      """ Listen for events based on config. """
      event_type = config.get(CONF_EVENT_TYPE)
  
      if event_type is None:
          _LOGGER.error("Missing configuration key %s", CONF_EVENT_TYPE)
          return False
  
      event_data = config.get(CONF_EVENT_DATA)
  
      def handle_event(event):
          """ Listens for events and calls the action when data matches. """
          if not event_data or all(val == event.data.get(key) for key, val
                                   in event_data.items()):
              action()
  
      hass.bus.listen(event_type, handle_event)
      return True
  
new_contents: """
  homeassistant.components.automation.event
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  Offers event listening automation rules.
  
  For more details about this automation rule, please refer to the documentation
  at https://home-assistant.io/components/automation.html#event-trigger
  """
  import logging
  
  CONF_EVENT_TYPE = "event_type"
  CONF_EVENT_DATA = "event_data"
  
  _LOGGER = logging.getLogger(__name__)
  
  
  def trigger(hass, config, action):
      """ Listen for events based on config. """
      event_type = config.get(CONF_EVENT_TYPE)
  
      if event_type is None:
          _LOGGER.error("Missing configuration key %s", CONF_EVENT_TYPE)
          return False
  
      event_data = config.get(CONF_EVENT_DATA)
  
      def handle_event(event):
          """ Listens for events and calls the action when data matches. """
          if not event_data or all(val == event.data.get(key) for key, val
                                   in event_data.items()):
              action()
  
      hass.bus.listen(event_type, handle_event)
      return True
  
subject: Add link to docs