{description: Indicates a value to assert as an if-none-exist header on a create or update action, package_name: hl7.fhir.us.davinci-crd, derivation: constraint, name: CDSHookServiceResponseExtensionIfNoneExist, type: string, package_version: 2.1.0-preview, class: primitive-type, kind: primitive-type, url: 'http://hl7.org/fhir/us/davinci-crd/StructureDefinition/CDSHookServiceResponseExtensionIfNoneExist', base: 'http://hl7.org/fhir/StructureDefinition/string', version: 2.1.0-preview}