code: def start_worker_watchdog(
      session, devices=None, ping_interval=60, shutdown_timeout=3600
  ):
      """Start global worker watchdog to shutdown workers on coordinator exit."""
      global _WATCHDOG
      if _WATCHDOG is None:
          # Ensure we can send a few pings before we timeout!
          ping_interval = min(shutdown_timeout / 10.0, ping_interval)
          _WATCHDOG = WatchdogManager(
              session, devices, ping_interval, shutdown_timeout
          )
          _WATCHDOG.configure_and_run()
  
imports: import threading
  import time
  from google.protobuf import text_format
  from tensorflow.core.protobuf import config_pb2
  from tensorflow.core.util import event_pb2
  from tensorflow.python.client import session
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.platform import tf_logging
  from tensorflow.python.tpu.ops import tpu_ops
  from tensorflow.python.training import session_run_hook
  from tensorflow.python.training import training_util
label_desc: Use image node_id 3 for calling a global function with example usage: start_worker_watchdog(session, devices, ping_interval, shutdown_timeout) without return types