code: def test_add(self):
      row = LLMFnOutputRow(data={"result": "none"}, result_type=str)
      row.add("score", 42)
      row.set_result_value("hello")
      self.assertEqual({"score": 42, "result": "hello"}, dict(row))
      self.assertEqual("result", row.result_key())
      self.assertEqual("hello", row.result_value())
  
file_path: generative-ai-python/tests/notebook/lib/test_llmfn_output_row.py
imports: from __future__ import annotations
  from typing import Any, Mapping
  from absl.testing import absltest
  from google.generativeai.notebook.lib import llmfn_output_row
label_desc: Use image node_id 6 for calling the LLMFnOutputRowTest obj's underlying member method code with example usage: obj.test_add() without return types