def cache(func):
    @wraps(func)
    def wrapper(obj, *args):
        key = args[0]
        value = _cache.get(key)
        if value:
            print('get it')
            return json.loads(value)
        rs = func(obj, *args)
        _cache.set(key, json.dumps(rs))
        return rs

    return wrapper

    @classmethod
    @cache
    def get(cls, id):
        rs = cls.objects.get(id=id)
        return {
            'id': rs.id,
            'username': rs.username,
            'age': rs.age,
            'email': rs.email,
            'info': rs.info,
            'create_time': str(rs.create_time),
            'update_time': str(rs.update_time)
        }