public void ContainsKey_ReturnsExpectedTruthiness()
        {
            var collection = new ResolvedVariableCollection();

            collection.AddVariable(new ResolvedVariable("key1", new GraphTypeExpression("BOB"), "bob"));

            Assert.IsTrue(collection.ContainsKey("key1"));
            Assert.IsFalse(collection.ContainsKey("key2"));
        }