code: def serialize(self, include_class=True, save_dynamic=False, **kwargs):
          
          json_dict = super(Singleton, self).serialize(
              include_class=include_class,
              save_dynamic=save_dynamic,
              **kwargs
          )
          json_dict['_singleton_id'] = self._singleton_id
          return json_dict
docs: Serialize Singleton instance to a dictionary.
  
          This behaves identically to HasProperties.serialize, except it also
          saves the identifying name in the dictionary as well.