def METHOD_NAME(self):
    """
    From the backport of the email package
    """
    s = b'From: foo@bar.com\nTo: baz\nMime-Version: 1.0\nContent-Type: text/plain; charset=utf-8\nContent-Transfer-Encoding: base64\n\ncMO2c3RhbA\xc3\xa1=\n'
    u = 'From: foo@bar.com\nTo: baz\nMime-Version: 1.0\nContent-Type: text/plain; charset=utf-8\nContent-Transfer-Encoding: base64\n\ncMO2c3RhbA\udcc3\udca1=\n'
    s2 = s.decode('ASCII', errors='surrogateescape')
    self.assertEqual(s2, u)