private static @Nullable PsiExpression getOnlyArgument(@NotNull PsiCallExpression expression) {
    PsiExpressionList argumentList = expression.getArgumentList();
    if (argumentList == null) return null;
    PsiExpression[] arguments = argumentList.getExpressions();
    if (arguments.length != 1) return null;
    return PsiUtil.skipParenthesizedExprDown(arguments[0]);
  }
private static @Nullable PsiExpression getOnlyArgument(@NotNull PsiCallExpression expression)