Switch to Python's new packaging system (PEP517)

[emfox]

Please consider switch to Python's new packaging system, according to PEP 517 & PEP 518.
https://peps.python.org/pep-0517/
https://peps.python.org/pep-0518/
these are the orignail PEP, and we have new guildeline from the same old URL:
https://packaging.python.org/en/latest/tutorials/packaging-projects/
or this one:
https://setuptools.pypa.io/en/latest/build_meta.html
in short, a new simple pyproject.toml would do the whole thing, and every kind of frontend or backend of new build systems will do the other tricks, and then remove setup.py or keep it for compatibility.

Here we have some background knowledge on why we should do this:
https://bernat.tech/posts/pep-517-518/
https://blog.ganssle.io/articles/2021/10/setup-py-deprecated.html

[emfox]

oh, and a transition guide if interest (a little old, I did not try it myself):
http://ivory.idyll.org/blog/2021-transition-to-pyproject.toml-example.html