docs: public ListStepsResponse listSteps(ListStepsRequest request) {
          checkNotNull(request, "request should not be null.");
          checkStringNotEmpty(request.getClusterId(), "The parameter clusterId should not be null or empty string.");
  
          InternalRequest internalRequest = this.createRequest(
                  request, HttpMethodName.GET, CLUSTER, request.getClusterId(), STEP);
          if (request.getMarker() != null) {
              internalRequest.addParameter("marker", request.getMarker());
          }
          if (request.getMaxKeys() >= 0) {
              internalRequest.addParameter("maxKeys", String.valueOf(request.getMaxKeys()));
          }
  
          return this.invokeHttpClient(internalRequest, ListStepsResponse.class);
      }