private static @Nullable PsiCaseLabelElement skipParenthesis(PsiCaseLabelElement e) {
    if (!(e instanceof PsiParenthesizedExpression)) return e;

    return PsiUtil.skipParenthesizedExprDown((PsiParenthesizedExpression)e);
  }
private static @Nullable PsiCaseLabelElement skipParenthesis(PsiCaseLabelElement e)