This is the CodeSystem that contains all the codes in Extension Style Codes (http://hl7.org/fhir/tools/CodeSystem/extension-style) and Extension Style Codes (http://hl7.org/fhir/tools/CodeSystem/extension-style). E.g. what you have to deal with if you get resources containing codes in either of them
Generated Narrative: CodeSystem 3e40c41b-fe3a-4441-94a6-9a868307c997-20
This code system http://hl7.org/fhir/comparison/CodeSystem/3e40c41b-fe3a-4441-94a6-9a868307c997-20 defines codes, but no codes are represented here