class_docstr: CLEAR Base Dataset for downloading / loading metadata
code: def _download_dataset(self) -> None:
      target_module = getattr(self.module, self.data_name)
  
      for name, base_url in target_module:
          if self.verbose:
              print("Downloading " + name + "...")
          url = os.path.join(base_url, name)
          self._download_and_extract_archive(
              url=url,
              file_name=name,
              checksum=None,
              remove_archive=True,
          )
  
imports: from pathlib import Path
  from typing import Optional, Sequence, Tuple, Union, List
  import json
  import os
  import torch
  from torchvision.datasets.folder import default_loader
  from avalanche.benchmarks.datasets import DownloadableDataset, default_dataset_location
  from avalanche.benchmarks.utils import default_flist_reader
  from avalanche.benchmarks.datasets.clear import clear_data
label_desc: Use image node_id 2 for calling the CLEARDataset obj's underlying member method code with example usage: obj._download_dataset() without return types