class_docstr: Generic dataset for images that can deal with PIL images, numpy arrays,
  or torch tensors.
code: def __len__(self):
      return len(self.images)
  
imports: import numpy
  import torch
  from torch.utils.data import Dataset
  from torchvision import datasets, transforms
  from typing import List, Union
  from pathlib import Path
  from PIL import Image
label_desc: Use image node_id 2 for calling the ImageDataset obj's underlying member method code with example usage: obj.__len__() and returns: len