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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 ack(self, tup):
 """Indicate that processing of a Tuple has succeeded. :param tup: the Tuple to acknowledge. :type tup: :class:`str` or :class:`pystorm.component.Tuple` """

        tup_id = tup.id if isinstance(tup, Tuple) else tup
        self.send_message({"command": "ack", "id": tup_id})