class_docstr: Produces [image, label] in Cifar10/100 dataset,
  image is 32x32x3 in the range [0,255].
  label is an int.
code: def __len__(self):
      return 50000 if self.train_or_test == "train" else 10000
  
imports: import numpy
  import os
  import pickle
  import tarfile
  from ...utils import logger
  from ...utils.fs import download, get_dataset_path
  from ..base import RNGDataFlow
label_desc: Use image node_id 2 for calling the CifarBase obj's underlying member method code with example usage: obj.__len__() and returns: unknown