code: def clean_sst_text(text):
      """Cleans tokens in the SST data, which has already been tokenized."""
      text = re.sub(r"[^A-Za-z0-9(),!?\'\`]", " ", text)
      text = re.sub(r"\s{2,}", " ", text)
      return text.strip().lower()
  
file_path: texar/examples/sentence_classifier/sst_data_preprocessor.py
imports: import os
  import re
  from io import open
  import tensorflow
  import texar.tf
label_desc: Use image node_id 1 for calling a global function with example usage: clean_sst_text(text) and returns: text