code: def get_data():
      ds = ConcatData([dataset.Mnist("train"), dataset.Mnist("test")])
      return BatchData(ds, BATCH)
  
file_path: tensorpack/examples/GAN/ConditionalGAN-mnist.py
imports: import argparse
  import numpy
  import os
  import cv2
  import tensorflow
  from tensorpack import *
  from tensorpack.dataflow import dataset
  from tensorpack.tfutils.scope_utils import auto_reuse_variable_scope
  from tensorpack.utils.viz import interactive_imshow, stack_patches
  from GAN import GANModelDesc, GANTrainer, RandomZData
label_desc: Use image node_id 2 for calling a global function with example usage: get_data() and returns: BatchData