def test_contains():
    os = OrderedSet(range(100))
    assert len(os) == 100
    for value in range(100):
        assert value in os
        assert os.count(value) == 1
    assert -1 not in os
    assert 100 not in os
def test_contains():
    os = OrderedSet(range(100))
    assert len(os) == 100
    for value in range(100):
        assert value in os
        assert os.count(value) == 1
    assert -1 not in os
    assert 100 not in os