code: def test_simple_methods(
      self,
      mock_to_file,
      mock_to_pyplot,
      mock_to_tensorboard,
      mock_to_visdom,
  ):
      callback = imaging.ImagingCallback()
      self.assertRaises(
          NotImplementedError, lambda: callback.on_batch("test")
      )
  
      callback = imaging.ImagingCallback().to_file("test")
      self.assertTrue(mock_to_file.call_count == 1)
  
      callback = imaging.ImagingCallback().to_pyplot()
      self.assertTrue(mock_to_pyplot.call_count == 1)
  
      callback = imaging.ImagingCallback().to_state("test")
      state = {}
      callback._handlers[0][0]("image", 0, state)
      self.assertTrue("test" in state)
      self.assertTrue(state["test"] is "image")
  
      callback = imaging.ImagingCallback().to_state(0)
      state = {}
      callback._handlers[0][0]("image", 0, state)
      self.assertTrue(0 in state)
      self.assertTrue(state[0] is "image")
  
      callback = imaging.ImagingCallback().to_tensorboard()
      self.assertTrue(mock_to_tensorboard.call_count == 1)
  
      callback = imaging.ImagingCallback().to_visdom()
      self.assertTrue(mock_to_visdom.call_count == 1)
  
imports: from unittest import TestCase
  from mock import MagicMock, patch, ANY
  import torch
  import torchbearer
  import torchbearer.callbacks.imaging
  import matplotlib.pyplot
label_desc: Use image node_id 5 for calling the TestImagingCallback obj's underlying member method code with example usage: obj.test_simple_methods(mock_to_file, mock_to_pyplot, mock_to_tensorboard, mock_to_visdom) without return types