public void TestEvery2WeeksOnFriday()
{
    Assert.Equal("At 12:00 PM, every 2 weeks, only on Friday", GetDescription("0 0 12 ? * FRI/2"));
}
[Fact]
public void TestEvery3WeeksWedThroughFri()
{
    Assert.Equal("At 12:00 PM, every 3 weeks, Wednesday through Friday", GetDescription("0 0 12 ? * WED-FRI/3"));
}
[Fact]
public void TestEvery4WeeksTueAndFri()
{
    Assert.Equal("At 12:00 PM, every 4 weeks, only on Tuesday and Friday", GetDescription("0 0 12 ? * TUE,FRI/4"));
}