public void Expire()
{
Cache.Memory.Strings.Set(KEY, SVALUE);
Assert.True(Cache.Memory.Strings.Exists(KEY));
Cache.Memory.Strings.Expire(KEY, TimeSpan.FromSeconds(1));
MemoryValue<string> result = Cache.Memory.Strings.Get<string>(KEY);
Assert.Equal(SVALUE, result.Value);
Thread.Sleep(1200);
MemoryValue<string> result2 = Cache.Memory.Strings.Get<string>(KEY);
Assert.False(result2.Exists);
Assert.Equal(null, result2.Value);
}