9c2468821e
This uses [teyit](https://pypi.org/project/teyit/) to modernize asserts, as recommended by the [unittest release notes](https://docs.python.org/3.12/whatsnew/3.12.html#id3). For example, `assertTrue(a == b)` is replaced with `assertEqual(a, b)`. This produces better error messages, e.g. `error: unexpectedly found 1 and 2 to be different` instead of `error: False`.