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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 acknowledged(self, value):
 """ Marks this message as acknowledged. :type value: Boolean :param value: if acknowledged """

        assert (isinstance(value, bool))
        self._acknowledged = value
        if value:
            self._timeouted = False
            self._rejected = False
            self._cancelled = False