docs: public static double getMaskingValueFromConfig(Map<String, Object> layerConfig,
                                                     KerasLayerConfiguration conf)
              throws InvalidKerasConfigurationException {
          Map<String, Object> innerConfig = KerasLayerUtils.getInnerLayerConfigFromConfig(layerConfig, conf);
          double maskValue = 0.0;
          if (innerConfig.containsKey(conf.getLAYER_FIELD_MASK_VALUE())) {
              try {
                  maskValue = (double) innerConfig.get(conf.getLAYER_FIELD_MASK_VALUE());
              } catch (Exception e) {
                  log.warn("Couldn't read masking value, default to 0.0");
              }
          } else {
              throw new InvalidKerasConfigurationException("No mask value found, field "
                      + conf.getLAYER_FIELD_MASK_VALUE());
          }
          return maskValue;
      }