what is difference between def write and def _write in odoo v12 community .
I can find there are 3 instances where in code of odoo v 12 community
instead of overriding write orm method _write is overriden .
1) account module -> account_invoice.py
2) base_automation module -> base_automation.py
3) sale module -> sale.py
so my question is what is difference between def write and def _write
and when to use def _write instead def write ??