code: def set_dataset_root(path):
      """Sets the root directory to download and cache datasets.
  
      There are two ways to set the dataset root directory. One is by setting the
      environment variable ``CHAINER_DATASET_ROOT``. The other is by using this
      function. If both are specified, one specified via this function is used.
      The default dataset root is ``$HOME/.chainer/dataset``.
  
      Args:
          path (str): Path to the new dataset root directory.
  
      """
      global _dataset_root
      _dataset_root = path
  
file_path: chainer/chainer/dataset/download.py
imports: import hashlib
  import os
  import shutil
  import sys
  import filelock
  from six.moves.urllib import request
  from chainer import utils
label_desc: Use image node_id 2 for calling a global function with example usage: set_dataset_root(path) without return types