code: def _add_readme_to_default_data_locations(data_dir=None, verbose=1):
      for d in get_data_dirs(data_dir=data_dir):
          file = Path(d) / "README.md"
          if file.parent.exists() and not file.exists():
              with open(file, "w") as f:
                  f.write(
                      """# Nilearn data folder
  
  This directory is used by Nilearn to store datasets
  and atlases downloaded from the internet.
  It can be safely deleted.
  If you delete it, previously downloaded data will be downloaded again."""
                  )
              if verbose > 0:
                  print(f"\nAdded README.md to {d}\n")
  
imports: import collections.abc
  import contextlib
  import fnmatch
  import hashlib
  import os
  import pickle
  import shutil
  import sys
  import tarfile
  import time
  import urllib
  import warnings
  import zipfile
  from pathlib import Path
  import numpy
  import requests
  from .._utils import fill_doc
  from .utils import get_data_dirs
label_desc: Use image node_id 9 for calling a global function with example usage: _add_readme_to_default_data_locations(data_dir, verbose) without return types