code: def test_load_state_dict(self):
      self.callback_1.load_state_dict = Mock(return_value="test_1")
      self.callback_2.load_state_dict = Mock(return_value="test_2")
  
      self.callback_1.state_dict = Mock(return_value="test_1")
      self.callback_2.state_dict = Mock(return_value="test_2")
  
      state = self.list.state_dict()
      self.list.load_state_dict(state)
  
      self.callback_1.load_state_dict.assert_called_once_with("test_1")
      self.callback_2.load_state_dict.assert_called_once_with("test_2")
  
      state = self.list.state_dict()
      state[CallbackList.CALLBACK_TYPES] = list(
          reversed(state[CallbackList.CALLBACK_TYPES])
      )
  
      with warnings.catch_warnings(record=True) as w:
          self.list.load_state_dict(state)
          self.assertTrue(len(w) == 1)
          self.assertTrue(issubclass(w[-1].category, UserWarning))
          self.assertTrue(
              "Callback classes did not match, expected: ['TensorBoard', 'Tqdm']"
              in str(w[-1].message)
          )
  
file_path: torchbearer/tests/callbacks/test_callbacks.py
imports: import warnings
  from unittest import TestCase
  from mock import MagicMock, Mock
  import torchbearer
  from torchbearer.callbacks import CallbackList, Tqdm, TensorBoard
label_desc: Use image node_id 3 for calling the TestCallbackList obj's underlying member method code with example usage: obj.test_load_state_dict() without return types