add typing + fix small issues

[leo-schick]

Add typing for parameters + fix several small issues in code

[jankatins]

LGTM...

Whats the minimum py version? It might be already enough for regular list[dict[str, str]] like annotations and x | None instead of Optiona[x]... Oh well, at some point, a pyupgrade/ruff run will fix that :-)

[leo-schick]

@jankatins I paid attention that I don't use all the fancy new stuff becuase we still have 3.6 as minimum requirement. I dropped 3.6 from the CI tests because it isn't anymore supported (and CI tests are not available anymore).

I often hesitate to upgrade because I don't know what people use out there.
x | None requires 3.10. I am currently on 3.9 because of some package dependecies which where incompatible when I tried to upgrade the last time.

Any suggestions for a policy when we should upgrade python versions?

[jankatins]

I think I remember that the initial mara version had python requirement on the "latest and greatest python" :-)

Basically up to you, but my suggestion would be to at least drop anything which is not supported anymore. Given that everybody and my mother runs stuff in a docker container that shouldn't be a big problem :-)

[leo-schick]

@jankatins Sounds great! I think I will merge this for now and we can apply this on e.g. next major release and make python 3.11 as a minimum requirement.