fastapi-cache2 не кэширует когда много вложенных объектов, возвращает пустой список как исправить? Может есть более адекватные пакеты?

class CityWithoutCountryID(BaseCity):
    id: PositiveInt = CityFields.id
    name: str = CityFields.name


class CountryWithCities(Country):
    cities: Union[List[CityWithoutCountryID], List] = []


class CountriesWithPagination(BaseCountry):
    items: Union[List[CountryWithCities], List[Country]] = []
    total: PositiveIntWithZero = ForPaginationFields.total
    page: PositiveIntWithZero = ForPaginationFields.page
    size: PositiveInt = ForPaginationFields.size

CountriesWithPagination он возвращает как:

{
  "items": [],
  "total": 0,
  "page": 0,
  "size": 10
}

без декоратора кэширования:

{
  "items": [
    {
      "id": 1,
      "name": "Guatemala",
      "cities": [
        {
          "id": 6,
          "name": "Josephville"
        },
        {
          "id": 11,
          "name": "South Brandon"
        }
      ]
    },
    {
      "id": 2,
      "name": "Cayman Islands",
      "cities": [
        {
          "id": 8,
          "name": "Lake Benjamin"
        }
      ]
    },
    {
      "id": 3,
      "name": "Kiribati",
      "cities": [
        {
          "id": 1,
          "name": "Edgarfurt"
        }
      ]
    },
    {
      "id": 4,
      "name": "Uganda",
      "cities": []
    },
    {
      "id": 5,
      "name": "Malaysia",
      "cities": []
    },
    {
      "id": 6,
      "name": "Christmas Island",
      "cities": [
        {
          "id": 3,
          "name": "Gregoryburgh"
        },
        {
          "id": 10,
          "name": "Port Timothybury"
        }
      ]
    },
    {
      "id": 7,
      "name": "Central African Republic",
      "cities": [
        {
          "id": 4,
          "name": "Port Cassandrafurt"
        }
      ]
    },
    {
      "id": 8,
      "name": "Denmark",
      "cities": []
    },
    {
      "id": 9,
      "name": "Cameroon",
      "cities": [
        {
          "id": 5,
          "name": "Lake Brianna"
        },
        {
          "id": 7,
          "name": "Gonzalezburgh"
        },
        {
          "id": 9,
          "name": "Brownfort"
        },
        {
          "id": 12,
          "name": "North Margaretview"
        }
      ]
    },
    {
      "id": 10,
      "name": "Nigeria",
      "cities": [
        {
          "id": 2,
          "name": "Stevensmouth"
        }
      ]
    }
  ],
  "total": 13,
  "page": 0,
  "size": 10
}

с меньшей вложенностью работает как надо