add custom url to a flask_peewee rest api

custom_rest_api.py

# coding=utf-8
from flask import request, Response
from peewee import *
from flask_peewee.rest import RestAPI
from models import *


class IntApi(RestAPI):
    @property
    def registry(self):
        return self._registry

    def get_urls(self):
        return [('/activity/<pk>/stats/', self.stats)]

    def stats(self, pk):
        query = (Run
                 .select(Run.id, UserInfo.info_field_1, UserInfo.info_field_2, UserInfo.info_field_3, FinalScore.score)
                 .join(UserInfo, JOIN.LEFT_OUTER,
                       on=((Run.uid == UserInfo.uid) & (Run.game == UserInfo.game)))
                 .join(FinalScore, JOIN.LEFT_OUTER,
                       on=((Run.run_id == FinalScore.run_id) & (Run.game == UserInfo.game)))
                 .where((Run.game == pk) & (FinalScore.score > 0))
                 .order_by(FinalScore.score.desc())
                 .dicts())
        kwargs = {} if request.is_xhr else {'indent': 2}
        return Response(json.dumps(list(query), **kwargs), mimetype='application/json')