docs: public void marshall(FunctionCode functionCode, ProtocolMarshaller protocolMarshaller) {
  
          if (functionCode == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(functionCode.getZipFile(), ZIPFILE_BINDING);
              protocolMarshaller.marshall(functionCode.getS3Bucket(), S3BUCKET_BINDING);
              protocolMarshaller.marshall(functionCode.getS3Key(), S3KEY_BINDING);
              protocolMarshaller.marshall(functionCode.getS3ObjectVersion(), S3OBJECTVERSION_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }