You can also define an automated action for this. Activate developer mode and go to Settings > Technical > Automated Actions (under Automation). You can define an automated action with a Trigger Condition of On Creation for any model in the system. One of the actions that can be performed (Action To Do) is Execute Python Code. This feature comes very handy for simple requirements.

you can intercept all the create at def _create of models.py
https://github.com/odoo/odoo/blob/12.0/odoo/models.py#L3618​