Is there a way to override the population of an item from a form on edit and/or create on Flask AppBuilder?

On Flask-Admin there is a method called update_model that can be overridden, and I am looking for a behavior like that. So that I can have access to both the item that is being create (the model’s instance) and the form with its data.

For the moment I’ve only found the method pre_add (and its equivalent pre_update) but they don’t have access to the form and its data. What would be the leanest way to implement a behavior similar to update_model ?