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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 check_for_expire_acknowledge(self):
 """ If have acknowledge and is expired, delete it :return: None """

        if (self.acknowledgement and
                self.acknowledgement.end_time != 0 and
                self.acknowledgement.end_time < time.time()):
            self.unacknowledge_problem()