code: def load_data(location="/tmp/.zoo/dataset/mnist"):
      (train_images, train_labels) = read_data_sets(location, "train")
      (test_images, test_labels) = read_data_sets(location, "test")
  
      return (train_images, train_labels), (test_images, test_labels)
  
file_path: analytics-zoo/pyzoo/zoo/pipeline/api/keras/datasets/mnist.py
imports: import gzip
  import numpy
  from bigdl.dataset import base
label_desc: Use image node_id 5 for calling a global function with example usage: load_data(location) and returns: train_images,  train_labels,  test_images,  test_labels