{description: Return prescriptions written on this date, package_name: hl7.fhir.r6.core, name: datewritten, type: date, package_version: 6.0.0-ballot4, class: unknown, kind: null, url: 'http://hl7.org/fhir/SearchParameter/VisionPrescription-datewritten', version: 6.0.0-ballot4}