public void EmptyExpiredTest()
{
var url2 = "url2";
//Saves the cache and pass it a timespan for expiration
barrel.Add(key: url, data: monkeys, expireIn: TimeSpan.FromDays(1));
barrel.Add(key: url2, data: monkeys, expireIn: TimeSpan.FromDays(-1));
Assert.IsTrue(barrel.Exists(url));
Assert.IsTrue(barrel.Exists(url2));
barrel.EmptyExpired();
Assert.IsTrue(barrel.Exists(url));
Assert.IsFalse(barrel.Exists(url2));
}