Процент продажи

1async function getCartSalePercentage() {
2   const baseUrl = 'http://apilocal.stableproxy.com/v2';
3   const req = await fetch(baseUrl + '/cart/sale-percentage', {
4         method: 'GET',
5         headers: {
6            'Content-Type': 'application/json'
7         }
8      }
9   );
10   
11   const res = await req.json();
12}