class_docstr: CLEAR Image Dataset (base class for CLEARImage)
code: def __len__(self):
      return len(self.targets)
  
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 7 for calling the _CLEARImage obj's underlying member method code with example usage: obj.__len__() and returns: len