That's a really, really hard question to answer without examining your setup.
Normally when people come here with IDLE problems someone tells them IDLE is crap, that they shouldn't use it, and then I come along and say, hey, it's not that bad but OS X is one of the most miserable programming environments in my experience that I will recommend you try something else. Not sure about Xcode's support, but Sublime Text is popular, I bet pycharm is on OS X (it's free, right?).
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