code: def allgather(tensor: tf.Tensor, name: str = None) -> tf.Tensor:
      """An op which concatenates the input tensor with the same input tensor on
      all other Bluefog processes.
  
      The concatenation is done on the first dimension, so the input tensors on the
      different processes must have the same rank and shape, except for the first
      dimension, which is allowed to be different.
  
      Arguments:
          tensor: A tensor to allgather.
          name: A name of the allgather operation.
  
      Returns:
        A tensor of the same type as `tensor`, concatenated on dimension zero
        across all processes. The shape is identical to the input shape, except for
        the first dimension, which may be greater and is the sum of all first
        dimensions of the tensors in different Bluefog processes.
      """
      if name is None and not _executing_eagerly():
          name = "BluefogAllgather_%s" % _normalize_name(tensor.name)
      return MPI_LIB.bluefog_allgather(tensor, name=name)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import re
  import tensorflow
  from tensorflow.python.framework import load_library
  from tensorflow.python.framework import ops
  from tensorflow.python.platform import resource_loader
  from bluefog.common.basics import BlueFogBasics
  from bluefog.common.util import get_ext_suffix
  from bluefog.tensorflow.util import _executing_eagerly
label_desc: Use image node_id 9 for calling a global function with example usage: allgather(tensor, name) and returns: MPI_LIB