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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def alltoall(self, x, mesh_axis, split_axis, concat_axis):
 """Grouped alltoall. Args: x: a LaidOutTensor mesh_axis: an integer the mesh axis along which to group split_axis: an integer (the Tensor axis along which to split) concat_axis: an integer (the Tensor axis along which to concatenate) Returns: a LaidOutTensor """

    return self._collective_with_groups(
        x, [mesh_axis],
        functools.partial(
            alltoall_ring, split_axis=split_axis, concat_axis=concat_axis))