def get_recommendation_data(self):
     """Read and return recommendation data from RDS."""
     return retrieve_worker_result(rdb, self.request_id,
                                   'recommendation_v2')
 def get_stack_result(self):
     """Read and return stack result from RDS."""
     return retrieve_worker_result(rdb, self.request_id,
                                   'stack_aggregator_v2')