code: def test_init_with_nones(self, mock_backend_initialize):
      # This is also valid case for Cloud TPU on JAX
      distribution_lib.initialize()
      mock_backend_initialize.assert_called_once_with(None, None, None)
  
imports: import os
  from unittest import mock
  import numpy
  import pytest
  import tensorflow
  from keras import backend
  from keras import testing
  from keras.backend import distribution_lib
  from keras.distribution import distribution_lib
label_desc: Use image node_id 4 for calling the MultiProcessInitializeTest obj's underlying member method code with example usage: obj.test_init_with_nones(mock_backend_initialize) without return types