code: def _Execute(cmd, args, time_limit=-1, use_client_context=False, cwd=None):
    
    run = [cmd]
    run.extend(args)
    env = os.environ.copy()
    if use_client_context:
      env.pop("LD_LIBRARY_PATH", None)
      env.pop("PYTHON_PATH", None)
      context = "client"
    else:
      context = "system"
    logging.info("Executing %s in %s context.", " ".join(run), context)
    p = subprocess.Popen(
        run,
        stdin=subprocess.PIPE,
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        env=env,
        cwd=cwd)
  
    alarm = None
    if time_limit > 0:
      alarm = threading.Timer(time_limit, HandleAlarm, (p,))
      alarm.setDaemon(True)
      alarm.start()
  
    stdout, stderr, exit_status = b"", b"", -1
    start_time = time.time()
    try:
      stdout, stderr = p.communicate()
      exit_status = p.returncode
    except IOError:
      # If we end up here, the time limit was exceeded
      pass
    finally:
      if alarm:
        alarm.cancel()
        alarm.join()
  
    return (stdout, stderr, exit_status, time.time() - start_time)
docs: Executes cmd.