code: def diff(a, b):
      return np.sum(np.abs(a.asnumpy() - b.asnumpy()))
  
file_path: mxnet/tools/bandwidth/measure.py
imports: import os, sys
  import mxnet
  import logging
  import argparse
  import time
  import numpy
  from importlib import import_module
  from collections import namedtuple
  from functools import reduce
label_desc: Use image node_id 3 for calling a global function with example usage: diff(a, b) and returns: np