code: def normalize_answer(s):
      """Lower text and remove punctuation, articles and extra whitespace.
      This is from the official evaluate-v2.0.py in SQuAD.
      """
  
      def remove_articles(text):
          regex = re.compile(r"\b(a|an|the)\b", re.UNICODE)
          return re.sub(regex, " ", 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))))
  
imports: import numpy
  import gluonnlp.data.batchify
  import collections
  import dataclasses
  import mxnet
  from mxnet import np, npx
  from mxnet.gluon import nn
  from mxnet.gluon.nn import HybridBlock
  from dataclasses import dataclass
  from tqdm import tqdm
  from typing import Optional, List, Tuple
  from gluonnlp.data.tokenizers import BaseTokenizerWithVocab
  from gluonnlp.utils.preprocessing import match_tokens_with_char_spans
  from gluonnlp.layers import get_activation
  from gluonnlp.op import select_vectors_by_position
  from gluonnlp.attention_cell import masked_logsoftmax, masked_softmax
  import string
  import re
  import json
label_desc: Use image node_id 2 for calling a global function with example usage: normalize_answer(s) and returns: white_space_fix, re, str, str, text