def test_contains():
p1 = Permission(RolePermit('boss'), RolePermit('lackey'))
p2 = Permission(RolePermit('lackey'))
assert p2.issubset(p1)
assert p2 in p1
def test_permission_union_denial():
p1 = Permission(('a', 'b'))
p2 = Denial(('a', 'c'))
p3 = p1.union(p2)
assert p1.issubset(p3)
assert p2.issubset(p3)
