@reference_id.setter<EOL><INDENT>def reference_id(self, reference_id):<DEDENT>
if reference_id is None:<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>if len(reference_id) > <NUM_LIT>:<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>self._reference_id = reference_id<EOL>
Sets the reference_id of this Order.
A client specified identifier to associate an entity in another system with this order.

:param reference_id: The reference_id of this Order.
:type: str