code: def barrier_mode(cls, value):
      invalidInputError(
          isinstance(value, bool),
          "barrier_mode should either be True or False",
      )
      cls._barrier_mode = value
  
imports: from bigdl.dllib.utils.common import *
  from bigdl.dllib.utils.file_utils import callZooFunc
  from bigdl.dllib.utils.utils import set_python_home
  from bigdl.dllib.utils.log4Error import *
  import warnings
  import multiprocessing
  import os
  import threading
  import sys
label_desc: Use image node_id 4 for calling the ZooContextMeta obj's underlying member method code with example usage: obj.barrier_mode(cls, value) without return types