def test_mod_add():
a = Binary(234)
b = Binary(345)
c = Binary(500)
d = Binary(579)
assert a % b != c
assert a % b != d
d.set_size(len(b))
assert a % b == d
assert a.is_binary(a)
assert b.is_binary(b)
assert c.is_binary(c)
assert d.is_binary(d)
def test_set_size():
a = Binary('10101')
assert a.bits == '10101'
a.set_size(10)
assert a.bits == '0000010101'