Django: def save() in models.py

I’m trying to add the save-function inside my models.py, but it seems I’m doing something wrong. The user has to type the first- and last-name. Without him or her entering any more data, another field inside my models.py should be filled with a combination from these fields. models.py: Is this even possible? Thanks for all your help. Have a nice weekend! Answer Please don’t. This is redundant data. It turns out that keeping data in sync, even on the same database is more challening than it might look at first sight. Django has furthermore several functions like .update(…) [Django-doc] to