public Map<String,List<String>> extra() {
        return this.extra == null ? Map.of() : this.extra;
    }
@return extra contains extra attributes of the user that created the CertificateSigningRequest. Populated by the API server on creation and immutable.
sdk/java/src/main/java/com/pulumi/kubernetes/certificates/v1/outputs/CertificateSigningRequestSpecPatch.java