code: protected String getWord(CoreLabel label) {
      String word = label.getString(TextAnnotation.class);
      if (flags.wordFunction != null) {
        word = flags.wordFunction.apply(word);
      }
      return word;
    }
docs: Convenience methods for subclasses which use CoreLabel.  Gets the
  word after applying any wordFunction present in the
  SeqClassifierFlags.