code: def _AddEvent(self, event):
      
      if hasattr(event, 'event_data_row_identifier'):
        event_data_identifier = identifiers.SQLTableIdentifier(
            self._CONTAINER_TYPE_EVENT_DATA,
            event.event_data_row_identifier)
        lookup_key = event_data_identifier.CopyToString()
  
        event_data_identifier = self._event_data_identifier_mappings[lookup_key]
        event.SetEventDataIdentifier(event_data_identifier)
  
      # TODO: add event identifier mappings for event tags.
  
      self._storage_writer.AddEvent(event)
docs: Adds an event.
  
      Args:
        event (EventObject): event.