code: def restart(self):
      assert not self.is_alive()
      work = self._work_runner.work
      # un-wrap ProxyRun.
      is_proxy = isinstance(work.run, ProxyWorkRun)
      if is_proxy:
          work_run = work.run
          work.run = work_run.work_run
      work._restarting = True
      self.start()
      if is_proxy:
          work.run = work_run
  
imports: import multiprocessing
  from typing import Any, List, Optional
  import lightning.app
  from lightning.app.core import constants
  from lightning.app.core.queues import QueuingSystem
  from lightning.app.runners.backends.backend import Backend, WorkManager
  from lightning.app.utilities.enum import WorkStageStatus
  from lightning.app.utilities.network import _check_service_url_is_ready, find_free_network_port
  from lightning.app.utilities.port import disable_port, enable_port
  from lightning.app.utilities.proxies import ProxyWorkRun, WorkRunner
label_desc: Use image node_id 4 for calling the MultiProcessWorkManager obj's underlying member method code with example usage: obj.restart() without return types