Dostępne kraje Koszyk

async function getCartAvailableCountries() {
   const baseUrl = 'https://api.stableproxy.com/v2';
   const req = await fetch(baseUrl + '/cart/available-countries?' + Object.entries({
         "service": 49
      }).map(([key, value]) => key + "=" + value).join('&'), {
         method: 'GET',
         headers: {
            'Content-Type': 'application/json'
         }
      }
   );
   
   const res = await req.json();
}