code: def exit_tensorflow(sess=None, port=6006):
      
      text = "[TL] Close tensorboard and nvidia-process if available"
      text2 = "[TL] Close tensorboard and nvidia-process not yet supported by this function (tl.ops.exit_tf) on "
  
      if sess is not None:
          sess.close()
  
      if _platform == "linux" or _platform == "linux2":
          tl.logging.info('linux: %s' % text)
          os.system('nvidia-smi')
          os.system('fuser ' + port + '/tcp -k')  # kill tensorboard 6006
          os.system("nvidia-smi | grep python |awk '{print $3}'|xargs kill")  # kill all nvidia-smi python process
          _exit()
  
      elif _platform == "darwin":
          tl.logging.info('OS X: %s' % text)
          subprocess.Popen(
              "lsof -i tcp:" + str(port) + "  | grep -v PID | awk '{print $2}' | xargs kill", shell=True
          )  # kill tensorboard
      elif _platform == "win32":
          raise NotImplementedError("this function is not supported on the Windows platform")
  
      else:
          tl.logging.info(text2 + _platform)
docs: Close TensorFlow session, TensorBoard and Nvidia-process if available.
  
      Parameters
      ----------
      sess : Session
          TensorFlow Session.
      tb_port : int
          TensorBoard port you want to close, `6006` as default.