code: def prepare_mnist(data_dir: Path):
      print("Preparing MNIST...")
      MNIST(str(data_dir / "mnist"), download=True)
      for file in glob.glob(
          str(data_dir / "mnist" / "**" / "*.gz"), recursive=True
      ):
          Path(file).unlink()
  
file_path: nni/test/vso_tools/pack_testdata.py
imports: import argparse
  import glob
  import os
  import random
  import shutil
  import subprocess
  import warnings
  from collections import defaultdict
  from pathlib import Path
  from torchvision.datasets import CIFAR10, MNIST, ImageNet
label_desc: Use image node_id 2 for calling a global function with example usage: prepare_mnist(data_dir) without return types