code: def _retrieve_svhn_training():
      url = "http://ufldl.stanford.edu/housenumbers/train_32x32.mat"
      return _retrieve_svhn("train.npz", url)
  
file_path: chainer/chainer/datasets/svhn.py
imports: import os
  import numpy
  import chainer
  from chainer.dataset import download
  from chainer.datasets import tuple_dataset
label_desc: Use image node_id 3 for calling a global function with example usage: _retrieve_svhn_training() and returns: _retrieve_svhn