public void TestBuilder()
        {
            IBuilder builder = new ConcreteBuilder();

            builder.BuildPartOne("Part 1");
            builder.BuildPartTwo("Part 2");
            builder.BuildPartThree("Part 3");

            var product = builder.GetProduct();

            Assert.AreEqual(product.PartOne, "Part 1");
            Assert.AreEqual(product.PartTwo, "Part 2");
            Assert.AreEqual(product.PartThree, "Part 3");
        }