def app_context_processor(self, f):
        """Like :meth:`Flask.context_processor` but for a blueprint.  Such a
        function is executed each request, even if outside of the blueprint.
        """
        self.record_once(lambda s: s.app.template_context_processors
            .setdefault(None, []).append(f))
        return f
Like :meth:`Flask.context_processor` but for a blueprint.  Such a
        function is executed each request, even if outside of the blueprint.