AsNeededCondition FHIR Extension

{
    "resourceType":"StructureDefinition",
    "id":"asNeededCondition",
    "url":"https://openmrs.org/fhir/StructureDefinition/asNeededCondition",
    "name":"asNeededCondition",
    "kind":"complex-type",
    "abstract":false,
    "status":"draft",
    "contextType":"resource",
    "type":"Extension",
    "baseDefinition":"http://hl7.org/fhir/StructureDefinition/Extension",
    "derivation":"constraint",
    "differential":{
        "element": [
            {
                "id":"Extension.url",
                "path":"Extension.url",
                "fixedUri":"https://openmrs.org/fhir/StructureDefinition/description"
            },
            {
                "id":"Extension.valueString",
                "path":"Extension.valueString",
                "type": [
                    {
                        "code":"string"
                    }
                ]
            }
        ]
    }
}