def _get_normalized_set(vocab):
  """Build set of special token ids to ignore when computing matching metrics.

  Args:
    vocab: An instance of text_utils.Vocab.

  Returns:
    remove: A set of wordpiece token indices to ignore.
  """
  punct = {vocab.t2i(t) for t in string.punctuation if t in vocab}
  articles = {vocab.t2i(t) for t in ["a", "an", "the"] if t in vocab}
  plural = {vocab.t2i(t) for t in ["##s"] if t in vocab}
  contractions = {vocab.t2i(t) for t in ["s", "'s"] if t in vocab}
  remove = punct | articles | plural | contractions | {0}
  return remove
Build set of special token ids to ignore when computing matching metrics.

  Args:
    vocab: An instance of text_utils.Vocab.

  Returns:
    remove: A set of wordpiece token indices to ignore.
  
language/capwap/utils/reward_utils.py