code: def read_info_file(data_dir: str, info_file: str) -> torch.Tensor:
      """Return a Tensor containing the list of labels
      Read the file and keep only the ID of the 3D point.
      """
      with open(os.path.join(data_dir, info_file)) as f:
          labels = [int(line.split()[0]) for line in f]
      return torch.LongTensor(labels)
  
file_path: vision/torchvision/datasets/phototour.py
imports: import os
  from typing import Any, Callable, List, Optional, Tuple, Union
  import numpy
  import torch
  from PIL import Image
  from .utils import download_url
  from .vision import VisionDataset
label_desc: Use image node_id 2 for calling a global function with example usage: read_info_file(data_dir, info_file) and returns: torch