test on 3.14

[graingert]

Changes

Fixes #.

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* Fix big bad boo-boo in task groups (#123 <https://github.com/agronholm/anyio/issues/123>_; PR by @yourgithubaccount)

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[agronholm]

Isn't this a wee bit too early? Given that the CI will show a failed result if the 3.14 job fails.

[graingert]

There's an a0 release - so we should probably see what happens

[agronholm]

As expected, uvloop breaks the test suite.

[graingert]

As expected, uvloop breaks the test suite.

well they're depending on a attribute that cpython deprecated but didn't warn on lookup