code: def test_serializer_and_deserializer(self):
      history = trax_history.History()
      history.append("train", "metric1", 1, 0.1)
      json_object = history.to_dict()
      history2 = trax_history.History.from_dict(json_object)
      self.assertEqual(history2.get("train", "metric1"), [(1, 0.1)])
  
file_path: trax/trax/supervised/history_test.py
imports: from absl.testing import absltest
  from trax.supervised import history
label_desc: Use image node_id 3 for calling the HistoryTest obj's underlying member method code with example usage: obj.test_serializer_and_deserializer() without return types