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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_id(self, refund_id):
 """ Sets the refund_id of this AdditionalRecipientReceivableRefund. The ID of the refund that is associated to this receivable refund. :param refund_id: The refund_id of this AdditionalRecipientReceivableRefund. :type: str """


        if refund_id is None:
            raise ValueError("Invalid value for `refund_id`, must not be `None`")
        if len(refund_id) < 1:
            raise ValueError("Invalid value for `refund_id`, length must be greater than or equal to `1`")

        self._refund_id = refund_id