def test_union_overlap(self):
ss = StackSet(xrange(0, 10))
tt = StackSet(xrange(5, 20))
p = ss.union(tt)
assert len(p) == 20
q = tt.union(ss)
assert len(q) == 20
def test_union(self):
ss = StackSet(xrange(0,4))
tt = StackSet(xrange(6,9))
p = ss.union(tt)
assert len(p) == 7
