docs: public void marshall(CaptionLanguageMapping captionLanguageMapping, ProtocolMarshaller protocolMarshaller) {
  
          if (captionLanguageMapping == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(captionLanguageMapping.getCaptionChannel(), CAPTIONCHANNEL_BINDING);
              protocolMarshaller.marshall(captionLanguageMapping.getLanguageCode(), LANGUAGECODE_BINDING);
              protocolMarshaller.marshall(captionLanguageMapping.getLanguageDescription(), LANGUAGEDESCRIPTION_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }