def test_should_be_able_to_add_existing(self):
rrs = RoundRobinSet([1, 2, 3])
rrs.add(2)
assert list(rrs) == [1, 2, 3]
def test_should_be_able_to_add_new(self):
rrs = RoundRobinSet([1, 2, 3])
rrs.add(4)
assert list(rrs) == [1, 2, 3, 4]