docs: def _annotate_query(query, generate_dict):
      """Add annotations to the query to retrieve values required by field value generate
      functions."""
      annotate_key_list = []
      for field_name, annotate_dict in generate_dict.items():
          for annotate_name, annotate_func in annotate_dict["annotate_dict"].items():
              query = annotate_func(query)
              annotate_key_list.append(annotate_name)
      return query, annotate_key_list