Check if any alert exists using selenium with python

I’m trying to write a test with selenium in python language for a web page that manages users. In this page someone can add role for users and if a role exists while adding it, an alert raises. I don’t know if the alert is a javascript alert or an element of the web page. I want to automatically check the existence of the alert, because checking for the role in the list wastes time and has an enormous load. I tried this: