It would have been clever of me to leave an error in there, to make sure you were actually thinking about it and not just cutting and pasting. (If you don't think about it, you won't be able to do it for yourself the next time.) But no, the error was inadvertent; looking at it now, I'm pretty sure I have one too many right parentheses.

I think I see which one, too. However, it's never too late to lead the student to water: You look at it, and figure out which right paren doesn't belong. I'll help, if you come up with questions, but "I don't see it" isn't one of the questions; you have to show me you're thinking about it.