code: private double getEpsFromConfig(Map<String, Object> layerConfig) throws InvalidKerasConfigurationException {
          Map<String, Object> innerConfig = KerasLayerUtils.getInnerLayerConfigFromConfig(layerConfig, conf);
          if (!innerConfig.containsKey(LAYER_FIELD_EPSILON))
              throw new InvalidKerasConfigurationException(
                      "Keras BatchNorm layer config missing " + LAYER_FIELD_EPSILON + " field");
          return (double) innerConfig.get(LAYER_FIELD_EPSILON);
      }
docs: Get BatchNormalization epsilon parameter from Keras layer configuration.
  
  @param layerConfig dictionary containing Keras layer configuration
  @return epsilon
  @throws InvalidKerasConfigurationException Invalid Keras config