Strangely enough, I'm used to vote for reopening others' questions on SO, but since I'm new on this site, I can't really vote to reopen my question. (Since it's put on hold by a mod I don't think users can vote to reopen anyway?)
The reason for closing it is that the relevant code is not in the question. For some reason I forgot to do that and the question got closed. This is completely fair and I would do the same thing and now I have fixed my question.
The question is, how do they know I fixed it and reopen it? There doesn't seem to be a way for new users to notify mods at all... Or are they automatically added to the Review page?