No, not necessarily at all -- there's a ton of pure Python code in the standard library, so if you're adding to or making improvements there, no need to know C. And then there's documentation and other non-code issues too.

Perfect, thanks. Been wanting to contribute to Python upstream for a while now, but it's overwhelming every time I take a look. :)

Remember that status quo is the sane default. Much more important to fix bugs and add docs than to add features.