public void ThatDifferentcolorsCreateDifferentKeys()
        {
            var key1 = TestShirtLookupTable.CreateShirtLookupKey(Color.Black, Size.Large);
            var key2 = TestShirtLookupTable.CreateShirtLookupKey(Color.Blue, Size.Large);

            Assert.AreNotEqual(key1, key2);
        }
        public void ThatAShirtKeyWillBeTheSameForTheSameColorAndSize()
        {
            var key1 = TestShirtLookupTable.CreateShirtLookupKey(Color.Black, Size.Large);
            var key2 = TestShirtLookupTable.CreateShirtLookupKey(Color.Black, Size.Large);

            Assert.AreEqual(key1, key2);
        }