code: def test_classy_model_wrapper_instance(self):
      # Test that we return a ClassyModel without a wrapper_cls
      MyTestModel.wrapper_cls = None
      model = MyTestModel()
      self.assertEqual(type(model), MyTestModel)
      self.assertIsInstance(model, MyTestModel)
      self.assertIsInstance(model, ClassyModel)
      self.assertIsInstance(model, nn.Module)
  
      # Test that we return a ClassyModelWrapper when specified as the wrapper_cls
      # The object should still pass the insinstance check
      MyTestModel.wrapper_cls = ClassyModelWrapper
      model = MyTestModel()
      self.assertEqual(type(model), ClassyModelWrapper)
      self.assertIsInstance(model, MyTestModel)
      self.assertIsInstance(model, ClassyModel)
      self.assertIsInstance(model, nn.Module)
  
imports: import copy
  import os
  import shutil
  import tempfile
  import unittest
  import torch
  import torch.nn
  from classy_vision.generic.util import load_checkpoint
  from classy_vision.heads import FullyConnectedHead, IdentityHead
  from classy_vision.hooks import CheckpointHook
  from classy_vision.models import build_model, ClassyModel, ClassyModelWrapper, register_model
  from classy_vision.models.classy_model import _ClassyModelAdapter
  from classy_vision.tasks import build_task
  from classy_vision.trainer import LocalTrainer
  from test.generic.config_utils import get_fast_test_task_config, get_test_task_config
  from torchvision import models
label_desc: Use image node_id 6 for calling the TestClassyModel obj's underlying member method code with example usage: obj.test_classy_model_wrapper_instance() without return types