code: def _all_reduce(comm, var, division, inplace):
      comm.all_reduce(var, division=division, inplace=inplace)
  
imports: import glob
  import os
  import time
  import zipfile
  from collections import OrderedDict
  import nnabla
  import nnabla.utils.callback
  import nnabla.utils.load
  import numpy
  from contextlib2 import ExitStack
  from nnabla import available_contexts
  from nnabla.config import nnabla_config
  from nnabla.logger import logger
  from nnabla.parameter import save_parameters
  from nnabla.utils.cli.utility import NodeTimeInfoCollector
  from nnabla.utils.cli.utility import get_cpu_gpu_average_load
  from nnabla.utils.cli.utility import let_data_to_variable
  from nnabla.utils.cli.utility import lms_scheduler
  from nnabla.utils.cli.utility import load_train_state
  from nnabla.utils.cli.utility import measure_cpu_gpu_instant_load
  from nnabla.utils.cli.utility import save_optimizer_states
  from nnabla.utils.cli.utility import str_to_num
  from nnabla.utils.communicator_util import current_communicator, single_or_rankzero
  from nnabla.utils.nnp_format import nnp_version
  from nnabla.utils.progress import configure_progress, progress
  from six.moves import range
label_desc: Use image node_id 1 for calling a global function with example usage: _all_reduce(comm, var, division, inplace) without return types