class_docstr: Define an interface to make the IterableDatasets for text2img data chainable
class_docstr_tok: ["Define","an","interface","to","make","the","IterableDatasets","for","text2img","data","chainable"]
code: def __len__(self):
      # return self.iter_end - self.iter_start
      return self.end - self.start
  
file_path: ColossalAI/examples/images/diffusion/ldm/data/base.py
imports: import os
  import cv2
  import numpy
  import torch
  from torch.utils.data import IterableDataset
label_desc: Use image node_id 2 for calling the Txt2ImgIterableBaseDataset obj's underlying member method code with example usage: obj.__len__() and returns: unknown