public bool Add(Product item)
        {
            if (!this.CanAddItem(item))
            {
                return false;
            }

            this.bagWeigth += item.Weight;
            this.bagCost += item.Cost;
            this.products.Push(item);

            return true;
        }
 private bool CanAddItem(Product item)
 {
     return this.bagWeigth + item.Weight <= this.bagCapacity;
 }