code: def preprocess(x):
      bgr_mean = [103.939, 116.779, 123.68]
      red, green, blue = [x[:, i, :, :] for i in range(3)]
      return jn.stack(
          [blue - bgr_mean[0], green - bgr_mean[1], red - bgr_mean[2]],
          axis=1,
      )
  
file_path: objax/objax/zoo/vgg.py
imports: import functools
  import os
  from urllib import request
  import jax.numpy
  import numpy
  import objax
label_desc: Use image node_id 1 for calling a global function with example usage: preprocess(x) and returns: jn