[lozenge]

They should make `msg` a keyword-only argument on all the TestCase.assert* statements. It wouldn't be the first breaking change of this type.

Searching for announced breaking changes about arguments to Python included functions...

https://bugs.python.org/issue25628

https://bugs.python.org/issue29193

https://bugs.python.org/issue36492

https://bugs.python.org/issue29209