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