code: def _handle(self, req, client_address):
      if isinstance(req, RunCommandRequest):
          self._wait_cond.acquire()
          try:
              if self._command_thread is None:
                  # We only permit executing exactly one command, so this is idempotent.
                  self._command_thread = threading.Thread(
                      target=safe_shell_exec.execute,
                      args=(req.command, req.env),
                  )
                  self._command_thread.daemon = True
                  self._command_thread.start()
          finally:
              self._wait_cond.notify_all()
              self._wait_cond.release()
          return network.AckResponse()
  
      if isinstance(req, NotifyInitialRegistrationCompleteRequest):
          self._wait_cond.acquire()
          try:
              self._initial_registration_complete = True
          finally:
              self._wait_cond.notify_all()
              self._wait_cond.release()
          return network.AckResponse()
  
      if isinstance(req, CommandTerminatedRequest):
          self._wait_cond.acquire()
          try:
              terminated = (
                  self._command_thread is not None
                  and not self._command_thread.is_alive()
              )
          finally:
              self._wait_cond.release()
          return CommandTerminatedResponse(terminated)
  
      if isinstance(req, RegisterCodeResultRequest):
          self._fn_result = req.result
          return network.AckResponse()
  
      return super(BasicTaskService, self)._handle(req, client_address)
  
imports: import threading
  import time
  from bluefog.run.horovodrun.common.util import network
  from bluefog.run.horovodrun.common.util import safe_shell_exec
label_desc: Use image node_id 2 for calling the BasicTaskService obj's underlying member method code with example usage: obj._handle(req, client_address) and returns: super, network, network, CommandTerminatedResponse, network