Assigning attributes to test cases, which are functions, is easier done if the
test cases were to be decorated with e.g. @test. By doing so, the test cases
could also be represented by a metaclass to Mypy, enabling static type checking
and hinting on function attributes. Moreover this metaclass could implement
Protocols define some attributes that could be shares across several classes.

Attributes are also a way to configure the test case environment more easily,
reducing the boilerplate code.