def test_blobRSA(self):
        """
        Return the over-the-wire SSH format of the RSA public key.
        """
        self.assertEqual(
            keys.Key(self.rsaObj).blob(),
            common.NS(b'ssh-rsa') +
            common.MP(self.rsaObj.private_numbers().public_numbers.e) +
            common.MP(self.rsaObj.private_numbers().public_numbers.n)
            )

        Return the over-the-wire SSH format of the RSA public key.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_keys.py