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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 refund(self):
 """Issue a full refund for this order """

        from longclaw.utils import GATEWAY
        now = datetime.strftime(datetime.now(), "%b %d %Y %H:%M:%S")
        if GATEWAY.issue_refund(self.transaction_id, self.total):
            self.status = self.REFUNDED
            self.status_note = "Refunded on {}".format(now)
        else:
            self.status_note = "Refund failed on {}".format(now)
        self.save()