Hello,
a python application isn't a binary but a script. So to invoke such an application there need to be a shell script somewhere in PATH that invoke that script via python3 interpreter. Imagine an application with a GUI (qt, tikinter, gtk, ...).
On the upstream site modern python projects using pyproject.toml (only), some use setup.cfg.
There you can define "entry points" and the "pip" installer does generate a shell script based on that information and place it in PATH.
That is a nice mechanism when installing via pip.
On your site as distro maintainers. How do you take care of then when creating deb files?
When a project do follow modern python packaging standards using pyproject.toml/setup.cfg and doesn't offer any other explict start shell script. Do you use that pip mechanic for the deb package?
Or how do you create your shell scripts?
I don't have an real world example of a python application for that.
I only have an example of a project (backintime) that don't use pyproject.toml/setup.cfg and offer its own shell script. I'm part of the new maintainer team and we will evolve the project to current python packaging standards; which means using pyproject.toml.