http://hl7.org/fhir/StructureDefinition/valueset-expand-group|4.0.1

This extension declares a group of concepts that is generated into the ValueSet.expansion.contains hierarchy when the expansion is generated for a UI. THere is no inherent assigned meaning to the hierarchy; it is used to help the user navigate the concepts. Each group has a display and/or a code, and a list of members, which are either concepts in the value set, or other groups (by code).
{
  "description": "This extension declares a group of concepts that is generated into the ValueSet.expansion.contains hierarchy when the expansion is generated for a UI. THere is no inherent assigned meaning to the hierarchy; it is used to help the user navigate the concepts. Each group has a display and/or a code, and a list of members, which are either concepts in the value set, or other groups (by code).",
  "package": "hl7.fhir.r4.examples@4.0.1",
  "date": "2019-10-31T22:29:23Z",
  "derivation": "constraint",
  "publisher": "HL7",
  "fhirVersion": "4.0.1",
  "name": "expand-group",
  "mapping": [ {
    "uri": "http://hl7.org/v3",
    "name": "RIM Mapping",
    "identity": "rim"
  } ],
  "abstract": false,
  "type": "Extension",
  "experimental": null,
  "resourceType": "StructureDefinition",
  "fhirversion": null,
  "title": null,
  "versionAlgorithmCoding": null,
  "extension": [ {
    "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
    "valueCode": "vocab"
  }, {
    "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
    "valueInteger": 1
  } ],
  "status": "draft",
  "id": "1a1f20db-ea0c-5a88-87fd-8bd6f4be443a",
  "kind": "complex-type",
  "url": "http://hl7.org/fhir/StructureDefinition/valueset-expand-group",
  "identifier": null,
  "context": [ {
    "type": "element",
    "expression": "ValueSet.compose.include"
  } ],
  "versionAlgorithmString": null,
  "fhir_id": null,
  "version": "4.0.1",
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/Extension"
}