code: def _normalize_answer(s):
      def remove_articles(text):
          return re.sub(r"\b(a|an|the)\b", " ", text)
  
      def white_space_fix(text):
          return " ".join(text.split())
  
      def remove_punc(text):
          exclude = set(string.punctuation)
          return "".join(ch for ch in text if ch not in exclude)
  
      def lower(text):
          return text.lower()
  
      return white_space_fix(remove_articles(remove_punc(lower(s))))
  
file_path: megatron-lm/tasks/orqa/unsupervised/qa_utils.py
imports: import collections
  import logging
  import string
  import unicodedata
  from functools import partial
  from multiprocessing import Pool
  from typing import Tuple, List, Dict
  import regex
  from tasks.orqa.unsupervised.tokenizers import SimpleTokenizer
label_desc: Use image node_id 6 for calling a global function with example usage: _normalize_answer(s) and returns: white_space_fix, re, str, str, text