I don't really like types on the function declaration line.

Instead of this:

    def check_permission(user: User, perm: str, obj: BaseModel | None) -> bool:

I find it much nicer to read something this:

    """
    Check if user is allowed to drive a car
    :user: User             # The application's User model
    :perm: str              # Our magic permission string. Tab seperated.
    :obj : Basemodel | None # Base model of all our objects since 2017
    :returns bool           # True if the user is allowed to drive
    """
    def check_permission(user, perm, obj):

This way I can grok the code much faster and only have to look into the type declaration when I want to. Due to syntax highlighting, it will look really nice. Because the whole type part can be styled in a dimmer color which puts it into the background. And I can define a key combo to show/hide the whole type part.