code: def compare_models(caffe_preds, coreml_preds):
      max_relative_error = 0
      for i in range(len(coreml_preds)):
          max_den = max(
              1.0, np.abs(caffe_preds[i]), np.abs(coreml_preds[i])
          )
          relative_error = np.abs(
              caffe_preds[i] / max_den - coreml_preds[i] / max_den
          )
          if relative_error > max_relative_error:
              max_relative_error = relative_error
  
      print("maximum relative error: ", max_relative_error)
      return max_relative_error
  
imports: from __future__ import print_function
  import json
  import os
  import shutil
  import subprocess
  import tarfile
  import tempfile
  import unittest
  from subprocess import Popen
  import PIL.Image
  import numpy
  import pytest
  import coremltools
  from coremltools._deps import _HAS_KERAS2_TF
  from coremltools.models.utils import _macos_version, _is_macos
label_desc: Use image node_id 3 for calling a global function with example usage: compare_models(caffe_preds, coreml_preds) and returns: max_relative_error