code: def AddEventData(self, event_data):
      
      self._RaiseIfNotWritable()
  
      self._AddAttributeContainer(self._CONTAINER_TYPE_EVENT_DATA, event_data)
docs: Adds event data.
  
      Args:
        event_data (EventData): event data.
  
      Raises:
        IOError: when the storage file is closed or read-only.
        OSError: when the storage file is closed or read-only.