@reason.setter<EOL><INDENT>def reason(self, reason):<DEDENT>
if reason is None:<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>if len(reason) > <NUM_LIT>:<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>self._reason = reason<EOL>
Sets the reason of this CreateRefundRequest.
A description of the reason for the refund.  Default value: `Refund via API`

:param reason: The reason of this CreateRefundRequest.
:type: str