code: public void marshall(StepStatus stepStatus, ProtocolMarshaller protocolMarshaller) {
  
          if (stepStatus == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(stepStatus.getState(), STATE_BINDING);
              protocolMarshaller.marshall(stepStatus.getStateChangeReason(), STATECHANGEREASON_BINDING);
              protocolMarshaller.marshall(stepStatus.getFailureDetails(), FAILUREDETAILS_BINDING);
              protocolMarshaller.marshall(stepStatus.getTimeline(), TIMELINE_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }
docs: Marshall the given parameter object.