code: def test_make_grid(self, mock_grid):
      callback = imaging.ImagingCallback()
      callback.on_batch = lambda _: 10
      callback.make_grid(1, 2, True, 4, True, 6)
      callback.on_batch({})
      mock_grid.assert_called_once_with(
          10,
          nrow=1,
          padding=2,
          normalize=True,
          range=4,
          scale_each=True,
          pad_value=6,
      )
  
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 3 for calling the TestImagingCallback obj's underlying member method code with example usage: obj.test_make_grid(mock_grid) without return types