code: def __len__(self):
      return len(self.dataloader)
  
imports: import os
  import torch
  import numpy
  from PIL import Image
  from functools import partial
  from image_classification.autoaugment import AutoaugmentImageNetPolicy
  import torchvision.datasets
  import torchvision.transforms
label_desc: Use image node_id 4 for calling the PrefetchedWrapper obj's underlying member method code with example usage: obj.__len__() and returns: len