In CS class I had a only 10 lines long python script (everything else was commented out). It didn't work and I searched the bug for ca 20 minutes. I asked a class mate (who commented the other code out) if he could figure it out and he just says: "The indention of the comment is wrong". We had a discussion that it doesn't matter how to indent comments. In the end he selected all the lines, pressed tab and it just worked ?!?!