code: def __init__(self, backend, root_rank, device="", *args):
      super(BroadcastGlobalVariablesCallbackImpl, self).__init__(*args)
      self.backend = backend
      self.root_rank = root_rank
      self.device = device
      self.broadcast_done = False
  
imports: import warnings
  import byteps.tensorflow
  import tensorflow
label_desc: Use image node_id 1 to create a new BroadcastGlobalVariablesCallbackImpl object from inherited base classes: object with example: obj = BroadcastGlobalVariablesCallbackImpl(backend, root_rank, device)