public CheckoutListDto(CheckoutList checkoutList)
 {
     CheckoutListId = checkoutList.CheckoutListId;
     UserId = checkoutList.UserId;
     //TotalPrice = checkoutList.TotalPrice;
     CheckoutItems = new List<CheckoutItemDto>();
     foreach (CheckoutItem item in checkoutList.CheckoutItems)
     {
         CheckoutItems.Add(new CheckoutItemDto(item));
     }
 }
        public CheckoutList ToEntity()
        {
            CheckoutList checkOutList = new CheckoutList
            {
                CheckoutListId = CheckoutListId,
                UserId = UserId,
                //TotalPrice = TotalPrice,
                CheckoutItems = new List<CheckoutItem>()
            };

            foreach (CheckoutItemDto item in CheckoutItems)
            {
                checkOutList.CheckoutItems.Add(item.ToEntity());
            }

            return checkOutList;
        }