Ok. Let's use this 'feature'. Can you please aad a short explanation to the docstring: Proposal:
```python
"""
Return a version object, not saved in the database.

The version data of the new version object is populated with the data
set via motion.title, motion.text, motion.reason if these data are not given
as keyword arguments. If the data is not set in the motion attributes,
it is populated with the data from the last version object if such object exists.
"""
```