> I realize this is a bit more involved than “just” packaging the thing,
> but it will be useful in the long run.

I'm missing the big picture.  That's the main problem.  What will happen
when I run 'guix-package -i hello'?

AFAICT, '(build-system gnu-build-system)' calls 'gnu-build' with the
corresponding arguments.  But I can't find where this actually happens.

I assume that 'gnu-build' will call '%standard-phases' (from
'gnu-build-system.scm') if I don't specify any arguments.  Then
'%standard-phases' will call the functions like 'set-paths' and
'unpack'.  How does it really work?

Let's assume that I'll do the same in 'python-build-system.scm'.  Can I
reuse 'set-paths' and 'unpack'?  Should I write my own functions
instead?  How can I determine what environment variables and prefixes
should be used?

I've noticed that 'development/python-modules/generic/default.nix' uses
'easy_install'.  Should we use it?

Nikita