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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _service_observable_out_box(self, limit: int = None) -> int: """ Service at most `limit` number of messages from the observable's outBox. :return: the number of messages successfully serviced. """

        msg_count = 0
        while True:
            if limit and msg_count >= limit:
                break

            msg = self._observable.get_output()
            if not msg:
                break

            msg_count += 1
            msg, observer_ids = msg
            # TODO: it's assumed that all Observers are connected the same way as Validators
            self.sendToNodes(msg, observer_ids)
        return msg_count