public void when_not_contains_key()
        {
            var memory = new DuplicationMemory();
            var result = memory.DoWeRemember("MemId");

            Assert.IsFalse(result);
        }
        public void when_exist_key()
        {
            var memory = new DuplicationMemory();

            memory.Memorize("MemId");
            var result = memory.DoWeRemember("MemId");

            Assert.IsTrue(result);
        }
        public void when_forget_older()
        {
            var memory = new DuplicationMemory();

            memory.Memorize("MemId");
            memory.ForgetOlderThan(new TimeSpan(0));
            var result = memory.DoWeRemember("MemId");

            Assert.IsFalse(result);
        }