Flask-SQLAlchemy set per request isolation level

isolation_level.py

def isolation_level(level):
    """Return a Flask view decorator to set SQLAlchemy isolation level
    
    Usage::
        @main.route("/thingy/<id>", methods=["POST"])
        @isolation_level("SERIALIZABLE")
        def update_a_thing(id):
            ...
    """
    def decorator(view):
        def view_wrapper(*args, **kwargs):
            db.session.connection(execution_options={'isolation_level': level})
            return view(*args, **kwargs)
        return view_wrapper
    return decorator

Is this thing would be any helpful?
I don't have any idea if this is going to work
but isn't going to make it easier? instead of adding this decorator before all routes?

This code is not tested, not sure if this even works

@app.after_request
def after_request():
     db.session.connection(execution_options={'isolation_level': level})

I don't think this actually works in Flask-SQLAlchemy, I get the warning

SAWarning: Connection is already established for the given bind; execution_options ignored

because Flask-SQLAlchemy doesn't allow you to change the isolation level after the connection is established.