'signature() method should generate a signature'

def test_signature(self):

    signer = signing.Signer('predictable-secret')
    signer2 = signing.Signer('predictable-secret2')
    for s in ('hello', '3098247:529:087:', '\\u2019'.encode()):
        self.assertEqual(signer.signature(s), signing.base64_hmac((signer.salt + 'signer'), s, 'predictable-secret'))
        self.assertNotEqual(signer.signature(s), signer2.signature(s))
