code: def _heartbeat(self):
      while True:
          if self._exit_flag:
              return
          # if not self._main_thread.is_alive():
          #     return
          run_status = {
              run: True
              for run, status in self._run_status.items()
              if status in (RunStatus.QUEUED, RunStatus.RUNNING)
          }
          commands = self._api.agent_heartbeat(
              self._agent_id, {}, run_status
          )
          if commands:
              job = Job(commands[0])
              logger.debug(f"Job received: {job}")
              if job.type in ["run", "resume"]:
                  self._queue.put(job)
                  self._run_status[job.run_id] = RunStatus.QUEUED
              elif job.type == "stop":
                  self._stop_run(job.run_id)
              elif job.type == "exit":
                  self._exit()
                  return
          time.sleep(5)
  
imports: import ctypes
  import logging
  import os
  import queue
  import socket
  import threading
  import time
  import wandb
  from wandb import wandb_sdk
  from wandb.apis import InternalApi
  from wandb.sdk.launch.sweeps import utils
label_desc: Use image node_id 8 for calling the Agent obj's underlying member method code with example usage: obj._heartbeat() without return types