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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 setValidTo(self, value):
 """Custom setter method to calculate a `ValidTo` date based on the `ValidFrom` and `ExpirationInterval` field values. """


        valid_from = self.getValidFrom()
        valid_to = DateTime(value)
        interval = self.getExpirationInterval()

        if valid_from and interval:
            valid_to = valid_from + int(interval)
            self.getField("ValidTo").set(self, valid_to)
            logger.debug("Set ValidTo Date to: %r" % valid_to)
        else:
            # just set the value
            self.getField("ValidTo").set(self, valid_to)