def get_common_name(self):
        """Get a value suitable for use as CommonName in a subject, or None if no such value is found.

        This function returns a string representation of the first value that is not a DirectoryName,
        RegisteredID or OtherName.
        """

        for name in self.value:
            if isinstance(name, (x509.DirectoryName, x509.RegisteredID, x509.OtherName)):
                continue
            return name.value 

def test_othername(self):
        self.assertEqual(parse_general_name('otherName:2.5.4.3;UTF8:example.com'), x509.OtherName(
            NameOID.COMMON_NAME, b'example.com'
        )) 

def test_otherName_octetString(self):
        self.assertEqual(parse_general_name(
                         'otherName:1.3.6.1.4.1.311.25.1;OctetString:09CFF1A8F6DEFD4B85CE95FFA1B54217'),
                         x509.OtherName(
                         x509.oid.ObjectIdentifier('1.3.6.1.4.1.311.25.1'),
                         b'\x04\x10\t\xcf\xf1\xa8\xf6\xde\xfdK\x85\xce\x95\xff\xa1\xb5B\x17'))

        with self.assertRaisesRegex(ValueError, '^Incorrect otherName format: foobar$'):
            parse_general_name('otherName:foobar')

        with self.assertRaisesRegex(ValueError, '^Unsupported ASN type in otherName: MagicString$'):
            parse_general_name('otherName:1.2.3;MagicString:Broken')