{description: 'The practitioner, individual or organization who played a role in the vaccination', package_name: hl7.fhir.r6.search, name: performer, type: reference, package_version: 6.0.0-ballot1, class: unknown, kind: null, url: 'http://hl7.org/fhir/SearchParameter/Immunization-performer', version: 6.0.0-ballot1}