docs: public static ProcessPackage getOrCreate(ResourceTypePackageRegistry rtps) {
          ProcessPackage rtp = (ProcessPackage) rtps.get(ResourceType.BPMN2);
          if (rtp == null) {
              rtp = new ProcessPackage();
              // register the same instance for all types. There is no distinction
              rtps.put(ResourceType.BPMN2, rtp);
              rtps.put(ResourceType.DRF, rtp);
              rtps.put(ResourceType.CMMN, rtp);
          }
          return rtp;
      }