No, you write down a detailed proposal and send it to the python-ideas mailing list, which Guido mentioned in this post. The decision making process in Python is fair and egalitarian. It's useful to have a "dictator" to give the final rule on difficult decisions every once in a while, because we all are engineers who get bogged down in design alternatives which don't always end up being conclusive. Guido has never really forced himself on the community. Sure, any new ideas he brings to the table will be taken more seriously, but so would ideas brought by other senior core-devs. It's a meritocracy, after all!
