def test_fromAgentv3(self):
        """
        Test that keys are correctly generated from Agent v3 strings.
        """
        self._testPrivateFromString(keydata.privateRSA_agentv3, 'RSA',
                keydata.RSAData)
        self._testPrivateFromString(keydata.privateDSA_agentv3, 'DSA',
                keydata.DSAData)
        self.assertRaises(keys.BadKeyError, keys.Key.fromString,
                b'\x00\x00\x00\x07ssh-foo'+ b'\x00\x00\x00\x01\x01'*5)

        Test that keys are correctly generated from Agent v3 strings.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_keys.py