http://hl7.org/fhir/StructureDefinition/cqf-cqlAccessModifier|5.2.0

Indicates the access modifier (i.e. public or private) of a CQL declaration. When CQL library declarations are represented in FHIR structures such as ParameterDefinition, this extension represents the access modifier of the declaration.
typedestination
baseDefinitionhttp://hl7.org/fhir/StructureDefinition/Extension
typehttp://hl7.org/fhir/StructureDefinition/Extension
Extension.url.typehttp://hl7.org/fhir/StructureDefinition/uri
Extension.value[x].typehttp://hl7.org/fhir/StructureDefinition/code
Extension.value[x].binding.valueSethttp://terminology.hl7.org/ValueSet/cql-access-modifier