code: def main(args):
      vocab = build_vocab(
          json=args.caption_path, threshold=args.threshold
      )
      vocab_path = args.vocab_path
      with open(vocab_path, "wb") as f:
          pickle.dump(vocab, f)
      print("Total vocabulary size: {}".format(len(vocab)))
      print("Saved the vocabulary wrapper to '{}'".format(vocab_path))
  
file_path: pytorch-tutorial/tutorials/03-advanced/image_captioning/build_vocab.py
imports: import nltk
  import pickle
  import argparse
  from collections import Counter
  from pycocotools.coco import COCO
label_desc: Use image node_id 2 for calling a global function with example usage: main(args) without return types