http://hl7.org/fhir/StructureDefinition/event-performerFunction|5.2.0

Distinguishes the type of involvement of the performer in the event. For example, 'author', 'verifier' or 'responsible party'.

element_id	types
Extension
Extension.extension
Extension.url
Extension.value[x]	CodeableConcept
Extension
Extension.id	http://hl7.org/fhirpath/System.String
Extension.extension	Extension
Extension.url	http://hl7.org/fhirpath/System.String
Extension.value[x]	CodeableConcept