@property<EOL><INDENT>def payment_id(self):<DEDENT>
return self._payment_id<EOL>
Gets the payment_id of this V1Refund.
A Square-issued ID associated with the refund. For single-tender refunds, payment_id is the ID of the original payment ID. For split-tender refunds, payment_id is the ID of the original tender. For exchange-based refunds (is_exchange == true), payment_id is the ID of the original payment ID even if the payment includes other tenders.

:return: The payment_id of this V1Refund.
:rtype: str