        messageString = (
            'REGISTER sip:example.com SIP/2.0\r\n'
            'To: sip:<EMAIL>\r\n'
            'From: sip:<EMAIL>;tag=87321hj23128\r\n'
            'Max-Forwards: 8\r\n'
            'Call-ID: regaut01.0ha0isndaksdj\r\n'
            'CSeq: 9338 REGISTER\r\n'
            'Via: SIP/2.0/TCP 192.0.2.253;branch=z9hG4bKkdjuw\r\n'
            'Authorization: NoOneKnowsThisScheme opaque-data=here\r\n'
            'Content-Length:0\r\n'
            '\r\n'
        )

        messageString = (
            'REGISTER sip:example.com SIP/2.0\r\n'
            'To: sip:<EMAIL>\r\n'
            'From: sip:<EMAIL>;tag=87321hj23128\r\n'
            'Max-Forwards: 8\r\n'
            'Call-ID: regaut01.0ha0isndaksdj\r\n'
            'CSeq: 9338 REGISTER\r\n'
            'Via: SIP/2.0/TCP 192.0.2.253;branch=z9hG4bKkdjuw\r\n'
            'Authorization: NoOneKnowsThisScheme opaque-data=here\r\n'
            'Content-Length:0\r\n'
            '\r\n'
        )
