code: def normalize(train_x, val_x):
      mean = [0.5339, 0.4180, 0.4460]  # mean for malaria dataset
      std = [0.3329, 0.2637, 0.2761]  # std for malaria dataset
      train_x /= 255
      val_x /= 255
      for ch in range(0, 2):
          train_x[:, ch, :, :] -= mean[ch]
          train_x[:, ch, :, :] /= std[ch]
          val_x[:, ch, :, :] -= mean[ch]
          val_x[:, ch, :, :] /= std[ch]
      return train_x, val_x
  
file_path: singa/examples/malaria_cnn/data/malaria.py
imports: import numpy
  import os
  import sys
  from PIL import Image
label_desc: Use image node_id 5 for calling a global function with example usage: normalize(train_x, val_x) and returns: train_x,  val_x