def startReceivingBoxes(boxSender):
        """
        The L{IBoxReceiver.ampBoxReceived} method will start being called;
        boxes may be responded to by responding to the given L{IBoxSender}.

        @param boxSender: an L{IBoxSender} provider.
        """

        The L{IBoxReceiver.ampBoxReceived} method will start being called;
        boxes may be responded to by responding to the given L{IBoxSender}.

        @param boxSender: an L{IBoxSender} provider.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/protocols/amp.py