[zahlman]

cppreference.com is very, very good at being reference, as in the name.

Python's documentation is scattershot and incomplete in many places, and lacks a consistent copy-editing style - but it offers good coverage of all kinds of documentation (per the Diataxis framework), not just reference. The people writing that documentation explicitly take that framework into consideration and use it to look for ways to improve. (But it's still a volunteer effort that works basically the same way the code development does, following open-source principles, so.)