code: def testWorkerContinuousFailure(self):
      model = self._create_model_and_run_indefinitely()
  
      self.assertFalse(self.cluster_coord.done())
      self._cluster.kill_task("worker", 0)
      time.sleep(2)
      self.assertFalse(
          context.check_alive("/job:worker/replica:0/task:0")
      )
      self._cluster.start_task("worker", 0)
      time.sleep(2)
      self.assertTrue(
          context.check_alive("/job:worker/replica:0/task:0")
      )
      self._cluster.kill_task("worker", 0)
      time.sleep(2)
      self.assertFalse(
          context.check_alive("/job:worker/replica:0/task:0")
      )
      self._cluster.start_task("worker", 0)
      time.sleep(2)
      self.assertTrue(
          context.check_alive("/job:worker/replica:0/task:0")
      )
  
      model.join_training_functions()
      self.assertGreaterEqual(model.iterations.numpy(), 10)
  
imports: import gc
  import os
  import sys
  import threading
  import time
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.distribute import multi_worker_test_base
  from tensorflow.python.distribute import parameter_server_strategy_v2
  from tensorflow.python.distribute import test_util
  from tensorflow.python.distribute.cluster_resolver.cluster_resolver import SimpleClusterResolver
  from tensorflow.python.distribute.coordinator import cluster_coordinator
  from tensorflow.python.eager import context
  from tensorflow.python.eager import def_function
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import tensor
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import check_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import random_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import tf_logging
  from tensorflow.python.training import coordinator
  from tensorflow.python.training import server_lib
label_desc: Use image node_id 17 for calling the BaseFaultToleranceTest obj's underlying member method code with example usage: obj.testWorkerContinuousFailure() without return types