class_docstr: CLEAR Base Dataset for downloading / loading metadata
code: def _load_metadata(self) -> bool:
      if "_" in self.data_name:
          return self._load_metadata_old()
      else:
          return self._load_metadata_new()
  
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 3 for calling the CLEARDataset obj's underlying member method code with example usage: obj._load_metadata() and returns: self, self