code: def test_support_communication_backend_gpu(
      communicator_class, backend
  ):
      n_units = 1
      comm = create_communicator(
          communicator_class, mpi_comm, use_gpu=True
      )
      MultiNodeBatchNormalization(
          n_units, comm, communication_backend=backend
      )
  
imports: import chainer
  from chainer.backends.cuda import cupy
  import chainer.testing
  import chainer.utils
  import mpi4py.MPI
  import numpy
  import pytest
  from chainermn.communicators.naive_communicator import NaiveCommunicator
  from chainermn.communicators.pure_nccl_communicator import PureNcclCommunicator
  from chainermn.links import MultiNodeBatchNormalization
  from chainermn import nccl
label_desc: Use image node_id 10 for calling a global function with example usage: test_support_communication_backend_gpu(communicator_class, backend) without return types