I wish there was a 'Modern Python' tutorial that would walk me through all the new python stuff like this or the type declarations or the new libs, etc.
If you're not averse to books I'm yet again recommending "Robust Python" by Patrick Viafore and for more esoteric things like metaclasses I would recommend "Expert Python Programming, 3rd Edition" by Michal Jaworski & Tarek Ziade. It's not wholly dedicated to metaclasses, so there are tons more to learn from it as well.
I learned about metaclasses in "Fluent Python". An excellent book, but it predates typing, so that's not covered. Then again, I believe a second edition is on its way.