def _message_handler(self, message):
        """
        Low level method to check incoming messages.

        Ayatana indicators seem to register themselves by passing their object
        path rather than the service providing that object. We therefore need
        to identify the sender of the message in order to register the service.

        Returning False so senders receieve a reply (returning True prevents
        reply being sent)
        """
        if message.member != "RegisterStatusNotifierItem":
            return False

        # If the argument is not an object path (starting with "/") then we assume
        # it is the bus name and we don't need to do anything else.
        if not message.body[0].startswith("/"):
            return False

        if message.sender not in self._items:
            self._items.append(message.sender)
            if self.on_item_added is not None:
                self.on_item_added(message.sender, message.body[0])
            self.StatusNotifierItemRegistered(message.sender)
        return False

        Low level method to check incoming messages.

        Ayatana indicators seem to register themselves by passing their object
        path rather than the service providing that object. We therefore need
        to identify the sender of the message in order to register the service.

        Returning False so senders receieve a reply (returning True prevents
        reply being sent)
        
libqtile/widget/helpers/status_notifier/statusnotifier.py