Fixture test:
This is broken cause it's trying to find doctype after it has been
deleted (wut?)
It was working so far because cache wasn't cleared correctly so you'd
still find it from cache.
db.set_value test:
converted to use last query instead of patching SQL
refactor: clean up code to py39+ supported syntax
- f-strings instead of format
- latest typing support instead of pre 3.9 TitleCase
- remove UTF-8 declarations.
- many more changes
Powered by https://github.com/asottile/pyupgrade/ + manual cleanups
