code: def __init__(
      self, methodName="runTest"
  ):  # pylint: disable=invalid-name
      super(DynamicClusterTest, self).__init__(methodName)
      self._cached_server1 = server_lib.Server.create_local_server()
      self._cached_server2 = server_lib.Server.create_local_server()
      self._cached_server3 = server_lib.Server.create_local_server()
      self._cached_server4 = server_lib.Server.create_local_server()
  
      self._cached_server1_target = self._cached_server1.target[
          len("grpc://") :
      ]
      self._cached_server2_target = self._cached_server2.target[
          len("grpc://") :
      ]
      self._cached_server3_target = self._cached_server3.target[
          len("grpc://") :
      ]
      self._cached_server4_target = self._cached_server4.target[
          len("grpc://") :
      ]
  
      self.server_def_s1 = get_server_def(
          JOB_NAME,
          local_server_port=0,
          remote_server_addresses=[self._cached_server1_target],
          task_index=0,
      )
      self.server_def_s1_s2 = get_server_def(
          JOB_NAME,
          local_server_port=0,
          remote_server_addresses=[
              self._cached_server1_target,
              self._cached_server2_target,
          ],
          task_index=0,
      )
      self.server_def_s1_s3 = get_server_def(
          JOB_NAME,
          local_server_port=0,
          remote_server_addresses=[
              self._cached_server1_target,
              self._cached_server3_target,
          ],
          task_index=0,
      )
      self.server_def_s4_s3 = get_server_def(
          JOB_NAME,
          local_server_port=0,
          remote_server_addresses=[
              self._cached_server4_target,
              self._cached_server3_target,
          ],
          task_index=0,
      )
      self.server_def_s1_s2_s3 = get_server_def(
          JOB_NAME,
          local_server_port=0,
          remote_server_addresses=[
              self._cached_server1_target,
              self._cached_server2_target,
              self._cached_server3_target,
          ],
          task_index=0,
      )
      self.server_def_s1_s2_s3_s4 = get_server_def(
          JOB_NAME,
          local_server_port=0,
          remote_server_addresses=[
              self._cached_server1_target,
              self._cached_server2_target,
              self._cached_server3_target,
              self._cached_server4_target,
          ],
          task_index=0,
      )
  
      self.device_local = (
          "/job:%s/replica:0/task:0/device:CPU:0" % JOB_NAME
      )
      self.device_t1 = (
          "/job:%s/replica:0/task:1/device:CPU:0" % JOB_NAME
      )
      self.device_t2 = (
          "/job:%s/replica:0/task:2/device:CPU:0" % JOB_NAME
      )
      self.device_t3 = (
          "/job:%s/replica:0/task:3/device:CPU:0" % JOB_NAME
      )
      self.device_t4 = (
          "/job:%s/replica:0/task:4/device:CPU:0" % JOB_NAME
      )
  
imports: import os
  import threading
  from absl.testing import parameterized
  import numpy
  from tensorflow.core.distributed_runtime.preemption import gen_check_preemption_op
  from tensorflow.core.protobuf import cluster_pb2
  from tensorflow.core.protobuf import tensorflow_server_pb2
  from tensorflow.python import pywrap_tfe
  from tensorflow.python.eager import context
  from tensorflow.python.eager import def_function
  from tensorflow.python.eager import executor
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
  from tensorflow.python.training import coordinator
  from tensorflow.python.training import server_lib
label_desc: Use image node_id 1 to create a new DynamicClusterTest object from inherited base classes: test, parameterized with example: obj = DynamicClusterTest(methodName)