===========================
Thursday, February 25, 2016
===========================

Today I wrote the new module :mod:`lino_xl.lib.invoicing` which is a
reimplementation of :mod:`lino_cosi.lib.auto.sales`. Main advantages
are:

- Use a database table (an "invoicing plan"), not a virtual table
- Make it possible to generate other invoices than sales invoices

The rest of this post are just some work notes.

>>> import lino_xl.lib.invoicing
>>> import lino_xl.lib.courses
>>> from lino import startup
>>> # startup('lino_xl.projects.min2.settings.demo')
>>> startup('lino_voga.projects.roger.settings.demo')
>>> from lino.api import rt
>>> fk = rt.models.contacts.Role._meta.get_field('person')
>>> fk.rel.to
<class 'lino_voga.lib.contacts.models.Person'>


Exception: lino_voga.projects.roger.lib.courses plugin tries to extend unresolved model 'courses.Line'