def test_hmacsha2256(self):
        """
        When L{SSHCiphers._getMAC} is called with the C{b"hmac-sha2-256"} MAC
        algorithm name it returns a tuple of (sha256 digest object, inner pad,
        outer pad, sha256 digest size) with a C{key} attribute set to the
        value of the key supplied.
        """
        self.assertGetMAC(
            b"hmac-sha2-256", sha256, digestSize=32, blockPadSize=32)

        When L{SSHCiphers._getMAC} is called with the C{b"hmac-sha2-256"} MAC
        algorithm name it returns a tuple of (sha256 digest object, inner pad,
        outer pad, sha256 digest size) with a C{key} attribute set to the
        value of the key supplied.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_transport.py