Fixed documentation to work with project.toml instead of setup.py

[susuhahnml]

No description provided.

[rkaminsk]

@susuhahnml there is no need to support python 3.7 anymore. Just remove the importlib_metadata part. To get rid of the errors just run pre-commit.

[susuhahnml]

@rkaminsk SHould I also remove the case for python 3.7 in the code then? in the parser.py file

[rkaminsk]

@rkaminsk SHould I also remove the case for python 3.7 in the code then? in the parser.py file

Yes, please do this. Python 3.9 is the latest release still supported. It is not worth the headache to support earlier versions. We could even drop python 3.9 and go for 3.10 if this makes our lives easier.

[susuhahnml]

Read to merge (I think) @rkaminsk