Get pyupgrade to update the typing

[Illviljan]

Is your feature request related to a problem?

Use more up-to-date typing styles on all files. Will reduce number of imports and avoids big diffs when doing relatively minor changes because pre-commit/pyupgrade has been triggered somehow.

Related to #6240

Describe the solution you'd like

Add from __future__ import annotations on files with a lot of typing.
Let pyupgrade do the rest.

Describe alternatives you've considered

No response

Additional context

No response

[mathause]

You could go the other way round and run

find . -name "*.py" -exec pyupgrade --py39-plus {} \;

(or even --py310-plus ) and then manually add from __future__ import annotations to files that were updated. Should also update

xarray/.pre-commit-config.yaml

Line 26 in d47cf0c

- "--py37-plus"

to --py38-plus.

[headtr1ck]

Almost all files have from __future__ import annotations now and pyupgrade is doing its thing :)