code: public double getForgetBiasInitFromConfig(Map<String, Object> layerConfig, boolean train)
              throws InvalidKerasConfigurationException, UnsupportedKerasConfigurationException {
          Map<String, Object> innerConfig = KerasLayerUtils.getInnerLayerConfigFromConfig(layerConfig, conf);
          String kerasForgetBiasInit;
          if (innerConfig.containsKey(conf.getLAYER_FIELD_UNIT_FORGET_BIAS())) {
              kerasForgetBiasInit = LSTM_FORGET_BIAS_INIT_ONE;
          } else if (!innerConfig.containsKey(conf.getLAYER_FIELD_FORGET_BIAS_INIT())) {
              throw new InvalidKerasConfigurationException(
                      "Keras LSTM layer config missing " + conf.getLAYER_FIELD_FORGET_BIAS_INIT() + " field");
          } else {
              kerasForgetBiasInit = (String) innerConfig.get(conf.getLAYER_FIELD_FORGET_BIAS_INIT());
          }
          double init;
          switch (kerasForgetBiasInit) {
              case LSTM_FORGET_BIAS_INIT_ZERO:
                  init = 0.0;
                  break;
              case LSTM_FORGET_BIAS_INIT_ONE:
                  init = 1.0;
                  break;
              default:
                  if (train)
                      throw new UnsupportedKerasConfigurationException(
                              "Unsupported LSTM forget gate bias initialization: " + kerasForgetBiasInit);
                  else {
                      init = 1.0;
                      log.warn("Unsupported LSTM forget gate bias initialization: " + kerasForgetBiasInit
                              + " (using 1 instead)");
                  }
                  break;
          }
          return init;
      }
docs: Get LSTM forget gate bias initialization from Keras layer configuration.
  
  @param layerConfig dictionary containing Keras layer configuration
  @return LSTM forget gate bias init
  @throws InvalidKerasConfigurationException Unsupported Keras config