'When not passed a password, pw_encode is noop on the payload.'

def test_aes_encode_without_password(self):

    payload = u'\u66f4\u7a33\u5b9a\u7684\u4ea4\u6613\u5e73\u53f0'
    enc = pw_encode(payload, None)
    self.assertEqual(payload, enc)
