How to make sure all requests have permission?

def composed(*decs):
    def deco(f):
        is_decorated = False
        for dec in decs:
            if 'custom_decorator' in dec.__qualname__.split('.'):
                is_decorated = True
            f = dec(f)
        if not is_decorated:
            raise SomeError
        return f
    return deco


@composed(blueprint.route('/'), custom_decorator)
def get():
   pass