Hi,
it depends :). My two cents:
If you are packaging application (PAPT team):
* user is using it in CLI / Xorg
* user don't need to know it's written in Python
* Python modules are typically private, not usable by other applications/libraries
-> one binary package: foo
If you are packaging library (DPMT team):
* your package is typically not usable by user directly
* your package is typically dependency of other packages (Python applications/libraries)
-> as many binary packages as "language branches" we have, e.g. python-foo, python3-foo, pypy-foo
If you are packaging application with public library part (PAPT team):
* both of above
* user is using it in CLI / Xorg
* BUT package have library part, which can be used in other Python applications/libraries
-> as many binary packages as "language branches" we have, e.g. python-foo, python3-foo, pypy-foo + foo for application. "foo" package can contain more than entrypoints, but icons, menu items, ...
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