blueprints.py 文件源码

def record_once(self, func):
        """Works like :meth:`record` but wraps the function in another
        function that will ensure the function is only called once.  If the
        blueprint is registered a second time on the application, the
        function passed is not called.
        """
        def wrapper(state):
            if state.first_registration:
                func(state)
        return self.record(update_wrapper(wrapper, func))