@property<EOL><INDENT>def reference_id(self):<DEDENT>
return self._reference_id<EOL>
Gets the reference_id of this Transaction.
If the transaction was created with the [Charge](#endpoint-transactions-charge) endpoint, this value is the same as the value provided for the `reference_id` parameter in the request to that endpoint. Otherwise, it is not set.

:return: The reference_id of this Transaction.
:rtype: str