Test on Python 3.10-dev

[hugovk]

Python 3.10 is currently in its last beta with a release candidate due next week (2021-08-02).

• https://www.python.org/dev/peps/pep-0619/#release-schedule

This PR tests 3.10-dev on GitHub Actions, currently Python 3.10.0-beta.4.

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I put the versions in quotes in the yaml, because when 3.10 final is released and -dev is removed from 3.10-dev, quoteless 3.10 would evaluate to 3.1!

• https://dev.to/hugovk/the-python-3-1-problem-85g

[JelleZijlstra]

Thanks!

[cooperlees]

The float rounding indicates what a fail 3.10 is :P

[cooperlees]

Stoked we pass! Do we just avoid changing Pattern matching syntax today or we somehow understand it?

• I feel we need some code with Pattern matching in our test suite added - https://www.python.org/dev/peps/pep-0636/
• Also Union types - https://www.python.org/dev/peps/pep-0604/

I wonder if anyone has created a repo that has Python Code that uses every python syntactical feature under the sun - If not, we should create said repo and put it into primers config ...

https://docs.python.org/3.10/whatsnew/3.10.html

This is scope creep and we will merge before caring about this - Was just interested ...

[hugovk]

Do we just avoid changing Pattern matching syntax today or we somehow understand it?

It's not yet supported, see #2242.