docs: def _to_dict(self):
          """Return a json dictionary representing this model."""
          _dict = {}
          if hasattr(self, 'synonyms') and self.synonyms is not None:
              _dict['synonyms'] = [x._to_dict() for x in self.synonyms]
          if hasattr(self, 'pagination') and self.pagination is not None:
              _dict['pagination'] = self.pagination._to_dict()
          return _dict