Which cmi cross reference id is not related to any parking taxes?
SELECT cmi_cross_ref_id FROM cmi_cross_references EXCEPT SELECT cmi_cross_ref_id FROM parking_fines
SELECT cmi_cross_ref_id FROM cmi_cross_references EXCEPT SELECT cmi_cross_ref_id FROM parking_fines
[{'cmi_cross_ref_id': 2}, {'cmi_cross_ref_id': 8}, {'cmi_cross_ref_id': 41}, {'cmi_cross_ref_id': 48}, {'cmi_cross_ref_id': 49}, {'cmi_cross_ref_id': 59}, {'cmi_cross_ref_id': 65}, {'cmi_cross_ref_id': 75}, {'cmi_cross_ref_id': 77}, {'cmi_cross_ref_id': 83}, {'cmi_cross_ref_id': 95}, {'cmi_cross_ref_id': 99}, {'cmi_cross_ref_id': 100}, {'cmi_cross_ref_id': 101}, {'cmi_cross_ref_id': 102}, {'cmi_cross_ref_id': 103}, {'cmi_cross_ref_id': 104}, {'cmi_cross_ref_id': 105}, {'cmi_cross_ref_id': 106}]