class_docstr: unittest for NetworkMorphismTuner
      
class_docstr_tok: ["unittest","for","NetworkMorphismTuner"]
docstr: unittest for add_model function
          
docstr_tok: ["unittest","for","add_model","function"]
code: def test_add_model(self):
      """unittest for add_model function"""
  
      tuner = NetworkMorphismTuner()
      tuner.add_model(0.8, 0)
      ret = {"model_id": 0, "metric_value": 0.8}
      self.assertEqual(tuner.history[-1], ret)
  
imports: import json
  from unittest import TestCase, main
  from copy import deepcopy
  import torch
  from nni.algorithms.hpo.networkmorphism_tuner import NetworkMorphismTuner
  from nni.algorithms.hpo.networkmorphism_tuner.graph import graph_to_json, json_to_graph
  from nni.algorithms.hpo.networkmorphism_tuner.graph_transformer import to_deeper_graph, to_skip_connection_graph, to_wider_graph
  from nni.algorithms.hpo.networkmorphism_tuner.layers import layer_description_extractor
  from nni.algorithms.hpo.networkmorphism_tuner.nn import CnnGenerator
label_desc: Use image node_id 9 for calling the NetworkMorphismTestCase obj's underlying member method code with example usage: obj.test_add_model() without return types