code: def __len__(self):
      return len(self.data)
  
file_path: colossalai/examples/language/gpt/titans/dataset/webtext.py
imports: import json
  import os
  from typing import Optional
  import torch
  from torch.utils.data import Dataset
  from transformers import GPT2Tokenizer
  from colossalai.legacy.registry import DATASETS
label_desc: Use image node_id 2 for calling the WebtextDataset obj's underlying member method code with example usage: obj.__len__() and returns: len