def adjustWindow(self, channel, bytesToAdd):
        """
        Tell the other side that we will receive more data.  This should not
        normally need to be called as it is managed automatically.

        @type channel:      subclass of L{SSHChannel}
        @type bytesToAdd:   L{int}
        """
        if channel.localClosed:
            return # we're already closed
        self.transport.sendPacket(MSG_CHANNEL_WINDOW_ADJUST, struct.pack('>2L',
                                    self.channelsToRemoteChannel[channel],
                                    bytesToAdd))
        log.msg('adding %i to %i in channel %i' % (bytesToAdd,
            channel.localWindowLeft, channel.id))
        channel.localWindowLeft += bytesToAdd

        Tell the other side that we will receive more data.  This should not
        normally need to be called as it is managed automatically.

        @type channel:      subclass of L{SSHChannel}
        @type bytesToAdd:   L{int}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/ssh/connection.py