class_docstr: Synchronous batch normalization. Stats are synchronized across all workers during training. 
code: def call(self, *args, **kwargs):
      outputs = super(SyncBatchNormalization, self).call(
          *args, **kwargs
      )
      try:
          # A temporary hack for TF1 compatibility with Keras batch norm.
          # Ops are added to tf.GraphKeys.UPDATE_OPS manually to mimic
          # behavior of TF1 batch norm layer for use in control dependencies.
          for u in self.updates:
              tf.add_to_collection(tf.GraphKeys.UPDATE_OPS, u)
      except AttributeError:
          pass
      return outputs
  
file_path: horovod/horovod/tensorflow/sync_batch_norm.py
imports: import tensorflow
  from horovod.tensorflow.mpi_ops import _allreduce
  from horovod.tensorflow.mpi_ops import size, rank
  from horovod.tensorflow.mpi_ops import Sum
label_desc: Use image node_id 3 for calling the SyncBatchNormalization obj's underlying member method code with example usage: obj.call() and returns: outputs