def test_equality():
s, s2 = OrderedSet(), OrderedSet()
s.update(1, 2, 3, 4, 5, 6, 7)
s2.update(1, 2, 3, 4, 5, 6, 7)
assert s == s2
s2.remove(1)
s2.add(1)
assert not s == s2
def test_index_access():
s = OrderedSet()
s.update(1, 2, 3, 4, 5, 6, 7)
assert s[4] == s[-3] == 5
def test_len2():
s = OrderedSet()
s.update(1, 2, 1, 1, 1, 1, 3)
assert len(s) == 3