public void Clone()
        {
            HttpQueryString query = new HttpQueryString {
                { "rød", "grød" }
            };

            HttpQueryString copy = query.Clone();

            Assert.AreEqual(1, copy.Count);

            copy.Add("hello", "world");

            Assert.AreEqual("grød", query["rød"]);
            Assert.AreEqual("grød", copy["rød"]);

            Assert.AreEqual(null, query["hello"]);
            Assert.AreEqual("world", copy["hello"]);
        }