http://hl7.org/fhir/StructureDefinition/cqf-systemUserLanguage|4.0.1

Preferred language of the person using the system.
typedestination
baseDefinitionhttp://hl7.org/fhir/StructureDefinition/Extension
typehttp://hl7.org/fhir/StructureDefinition/Extension
Extension.value[x].typehttp://hl7.org/fhir/StructureDefinition/CodeableConcept
Extension.value[x].binding.valueSethttp://hl7.org/fhir/ValueSet/languages