code: public void postProcess(Sentence sentence)
      {
          List<Mention> mentions = new ArrayList<Mention>(sentence.getMentions());
          for (Mention mention : mentions)
          {
              if (ParenthesisPostProcessor.isMismatched(mention))
                  sentence.removeMention(mention);
          }
      }
docs: Removes {@link Mention}s which contain a mismatched parenthesis ("(" or ")"), square bracket ("[" or "]") or curly bracket ("{" or "}").