public void Get_Total_Price_For_Some_Items(int quantity, decimal amount)
        {
            ICatalogueItem item = new SimpleCatalogueItem();

            for (int i = 0; i < quantity; i++)
            {
                IItem fakeItem = new FakeItem1();
                item.Add(fakeItem);
            }
            Assert.That(amount.Equals(item.GetTotalPrice()));
        }