code: def _handle(self, req, client_address):
      if isinstance(req, RunCommandRequest):
          self._wait_cond.acquire()
          try:
              if self._command_thread is None:
                  # we add req.env to _command_env and make this available to the executed command
                  if self._command_env:
                      env = self._command_env.copy()
                      self._add_envs(env, req.env)
                      req.env = env
  
                  if self._verbose >= 2:
                      print(
                          "Task service executes command: {}".format(
                              req.command
                          )
                      )
                      if self._verbose >= 3:
                          for key, value in req.env.items():
                              if "SECRET" in key:
                                  value = "*" * len(value)
                              print(
                                  "Task service env: {} = {}".format(
                                      key, value
                                  )
                              )
  
                  # We only permit executing exactly one command, so this is idempotent.
                  self._command_abort = threading.Event()
                  self._command_stdout = (
                      Pipe() if req.capture_stdout else None
                  )
                  self._command_stderr = (
                      Pipe() if req.capture_stderr else None
                  )
                  args = (
                      req.command,
                      req.env,
                      self._command_abort,
                      self._command_stdout,
                      self._command_stderr,
                      self._index,
                      req.prefix_output_with_timestamp,
                  )
                  self._command_thread = in_thread(
                      self._run_command, args
                  )
          finally:
              self._wait_cond.notify_all()
              self._wait_cond.release()
          return network.AckResponse()
  
      if isinstance(req, StreamCommandOutputRequest):
          # Wait for command to start
          self.wait_for_command_start()
  
          # We only expect streaming each command output stream once concurrently
          if isinstance(req, StreamCommandStdOutRequest):
              return self.stream_output(self._command_stdout)
          elif isinstance(req, StreamCommandStdErrRequest):
              return self.stream_output(self._command_stderr)
          else:
              return CommandOutputNotCaptured()
  
      if isinstance(req, AbortCommandRequest):
          self._wait_cond.acquire()
          try:
              if self._command_thread is not None:
                  self._command_abort.set()
              if self._command_stdout is not None:
                  self._command_stdout.close()
              if self._command_stderr is not None:
                  self._command_stderr.close()
          finally:
              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, CommandExitCodeRequest):
          self._wait_cond.acquire()
          try:
              terminated = (
                  self._command_thread is not None
                  and not self._command_thread.is_alive()
              )
              return CommandExitCodeResponse(
                  terminated,
                  self._command_exit_code if terminated else None,
              )
          finally:
              self._wait_cond.release()
  
      if isinstance(req, WaitForCommandExitCodeRequest):
          self._wait_cond.acquire()
          try:
              while (
                  self._command_thread is None
                  or self._command_thread.is_alive()
              ):
                  self._wait_cond.wait(
                      max(req.delay, WAIT_FOR_COMMAND_MIN_DELAY)
                  )
              return WaitForCommandExitCodeResponse(
                  self._command_exit_code
              )
          finally:
              self._wait_cond.release()
  
      if isinstance(req, RegisterCodeResultRequest):
          self._fn_result = req.result
          return network.AckResponse()
  
      return super(BasicTaskService, self)._handle(req, client_address)
  
imports: import abc
  import threading
  from horovod.runner.common import util
  from horovod.runner.common.util import network, safe_shell_exec, timeout
  from horovod.runner.util.streams import Pipe
  from horovod.runner.util.threads import in_thread
label_desc: Use image node_id 4 for calling the BasicTaskService obj's underlying member method code with example usage: obj._handle(req, client_address) and returns: super, network, network, network, network, self, CommandExitCodeResponse, WaitForCommandExitCodeResponse, self, CommandOutputNotCaptured