private IEnumerable<Product> AvailableProducts()
        {
            var products = new List<Product>();

            Product car = new Product
            {
                ProductId = 200,
                ProductType = "Beetle",
                Name = "Volkswagon Beetle",
                Description = "The coolest car on the planet, or at least was back in the 70's.",
                Price = 26000,
                ProductImage = "Beetle_Blue.jpg",
                AvailableColors = new List<string> { "Blue", "Red", "White", "Yellow" }
            };

            Product jet = new Product
            {
                ProductId = 220,
                ProductType="Jet",
                Name = "Honda HA-420",
                Description = "Kind of like a motorcycle, except it's an airplane and it flies really fast.",
                Price = 983900,
                ProductImage = "Jet_Blue.jpg",
                AvailableColors = new List<string> { "Blue", "Red", "Yellow" }
            };

            Product cup = new Product
            {
                ProductId = 230,
                ProductType = "Cup",
                Name = "Coffee Cup",
                Description = "You grab this in the morning, add primo coffee and two shots expresso and WOW what a great day!",
                Price = 6.99m,
                ProductImage = "Cup_Blue.jpg",
                AvailableColors = new List<string> { "Blue", "Green", "Orange", "Black" }
            };

            Product cake = new Product
            {
                ProductId = 240,
                ProductType = "Cake",
                Name = "Elegant Cake",
                Description = "Imagine the glory of eating one of these, or having friends over and they see this in the kitchen!",
                Price = 420,
                ProductImage = "Cake_Blue.jpg",
                AvailableColors = new List<string> { "Blue","Turquoise","Brown","Pink","Purple","White","Yellow" }
            };

            products.Add(car);
            products.Add(jet);
            products.Add(cup);
            products.Add(cake);

            return products;
        }
        private List<Product> RepeatedProductsList()
        {
            var repeatedProducts = new List<Product>();

            var product1 = new Product { ProductId = 123, ProductType = "Computer", Name = "Microsoft Surface Pro 3" };
            var product2 = new Product { ProductId = 456, ProductType = "Clothing", Name = "Blue Sock" };
            var product3 = new Product { ProductId = 789, ProductType = "Bedding", Name = "Flannel Sheets" };
            var product4 = new Product { ProductId = 444, ProductType = "Clothing", Name = "Blue Sock" }; // symptomatic of bad data.

            repeatedProducts.Add(product1);
            repeatedProducts.Add(product2);
            repeatedProducts.Add(product3);
            repeatedProducts.Add(product4);

            return repeatedProducts;
        }