Intersection of http://terminology.hl7.org/ValueSet/Languages and http://hl7.org/fhir/us/core/ValueSet/simple-language
This is the ValueSet that contains codes in both Languages (http://terminology.hl7.org/ValueSet/Languages) and Language codes with language and optionally a region modifier (http://hl7.org/fhir/us/core/ValueSet/simple-language).