code: def test_initialize_with_env_vars(self, mock_backend_initialize):
      job_addresses = "10.0.0.1:1234,10.0.0.2:2345"
      num_processes = 2
      current_process_id = 0
      os.environ["KERAS_DISTRIBUTION_JOB_ADDRESSES"] = job_addresses
      os.environ["KERAS_DISTRIBUTION_NUM_PROCESSES"] = str(
          num_processes
      )
      os.environ["KERAS_DISTRIBUTION_PROCESS_ID"] = str(
          current_process_id
      )
  
      distribution_lib.initialize()
      mock_backend_initialize.assert_called_once_with(
          job_addresses, num_processes, current_process_id
      )
  
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 3 for calling the MultiProcessInitializeTest obj's underlying member method code with example usage: obj.test_initialize_with_env_vars(mock_backend_initialize) without return types