code: def _get_instance(self, **kwargs):
          '''Return the first existing instance of the response record.
          '''
          return session.query(self.response_class).filter_by(**kwargs).first(f _get_instance(self, **kwargs):
          '''Return the first existing instance of the response record.
          '''
          return session.query(self.response_class).filter_by(**kwargs).first()
docs: Return the first existing instance of the response record.