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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 __recv_cb(self, msg):
 """Calls user-provided callback and marks message for Ack regardless of success """

        try:
            self.__msg_callback(msg)
        except:
            logger.exception("AmqpLink.__recv_cb exception calling msg_callback")
        finally:
            # only works if all messages handled in series
            self.__last_id = msg.delivery_tag
            self.__unacked += 1