code: def average_multi_gpu_blob(blob_name):
      """Return the average of a scalar blob held on multiple GPUs."""
      return sum_multi_gpu_blob(blob_name) / cfg.NUM_GPUS
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from __future__ import unicode_literals
  from collections import OrderedDict
  import cPickle
  import logging
  import numpy
  import os
  import pprint
  import yaml
  from caffe2.python import core
  from caffe2.python import workspace
  from detectron.core.config import cfg
  from detectron.core.config import load_cfg
  from detectron.utils.io import save_object
  import detectron.utils.c2
label_desc: Use image node_id 6 for calling a global function with example usage: average_multi_gpu_blob(blob_name) and returns: unknown