def _on_auth(self, user):
        if not user:
            self.abort(403)

        auth_id = user.pop('username', '') % 'friendfeed|%s'
        self.auth.login_with_auth_id(auth_id, remember=True,
            access_token=user.get('access_token'))
        return self._on_auth_redirect()
dataset/ETHPy150Open moraes/tipfy/examples/auth/app/handlers.py/FriendFeedAuthHandler._on_auth/swapped operands of `%`