def test_packetSTATUS(self):
        """
        A STATUS packet containing a result code, a message, and a language is
        parsed to produce the result of an outstanding request L{Deferred}.

        @see: U{section 9.1<http://tools.ietf.org/html/draft-ietf-secsh-filexfer-13#section-9.1>}
            of the SFTP Internet-Draft.
        """
        d = defer.Deferred()
        d.addCallback(self._cbTestPacketSTATUS)
        self.ftc.openRequests[1] = d
        data = struct.pack('!LL', 1, filetransfer.FX_OK) + common.NS(b'msg') + common.NS(b'lang')
        self.ftc.packet_STATUS(data)
        return d

        A STATUS packet containing a result code, a message, and a language is
        parsed to produce the result of an outstanding request L{Deferred}.

        @see: U{section 9.1<http://tools.ietf.org/html/draft-ietf-secsh-filexfer-13#section-9.1>}
            of the SFTP Internet-Draft.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_filetransfer.py