docs: def _to_dict(self):
          """Return a json dictionary representing this model."""
          _dict = {}
          if hasattr(self, 'gender') and self.gender is not None:
              _dict['gender'] = self.gender
          if hasattr(self, 'gender_label') and self.gender_label is not None:
              _dict['gender_label'] = self.gender_label
          if hasattr(self, 'score') and self.score is not None:
              _dict['score'] = self.score
          return _dict