code: def _normalize_text(text):
      text = text.lower()
      # Space around punctuation
      text = re.sub(
          "[%s]" % re.escape(string.punctuation), r" \g<0> ", text
      )
      text = re.sub(r"\s+", " ", text)
      text = text.strip()
      return text
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import json
  import math
  import os
  import re
  import string
  import tempfile
  import six
  from tensor2tensor.data_generators import generator_utils
  from tensor2tensor.data_generators import problem
  from tensor2tensor.data_generators import text_encoder
  from tensor2tensor.data_generators import tokenizer
  from tensor2tensor.data_generators.wikisum import utils
  from tensor2tensor.layers import modalities
  from tensor2tensor.utils import metrics
  from tensor2tensor.utils import registry
  import tensorflow.compat.v1
label_desc: Use image node_id 10 for calling a global function with example usage: _normalize_text(text) and returns: text