how to arrange classes in .py files?

[bearophileHUGS at lycos.com]

Kent:
> Now I just deal with my little application exactly in Java style:
> package: gui, service, dao, entity, util

If those things are made of a small enough number of sub things and
such sub things are small enough, then you may use a single module for
each of those Java packages (or even less).

My suggestion: try to write as little code as possible.
With practice you will see your Python code shrink a lot compared to
the Java one (but don't overdo it, one of the main qualities of Java
is long-term maintainability of code. And you can't do it if you write
Python in a code-golf-style :-) ).

Bye,
bearophile