code: def test_create_with_list_devices(self, mock_list_devices):
      distribution = distribution_lib.DataParallel()
      mock_list_devices.assert_called_once()
  
      device_mesh = distribution.device_mesh
      self.assertEqual(len(device_mesh.devices), 8)
      self.assertEqual(device_mesh.axis_names, ["batch"])
      self.assertEqual(distribution._batch_dim_name, "batch")
  
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 DataParallelDistributionTest obj's underlying member method code with example usage: obj.test_create_with_list_devices(mock_list_devices) without return types