code: public InputPreProcessor getInputPreprocessor(InputType... inputType) throws InvalidKerasConfigurationException {
          InputPreProcessor preprocessor = null;
          if (this.layer != null) {
              if (inputType.length > 1)
                  throw new InvalidKerasConfigurationException(
                          "Keras layer of type \"" + this.className + "\" accepts only one input");
              preprocessor = this.layer.getPreProcessorForInputType(inputType[0]);
          }
          return preprocessor;
      }
docs: Gets appropriate DL4J InputPreProcessor for given InputTypes.
  
  @param inputType Array of InputTypes
  @return DL4J InputPreProcessor
  @throws InvalidKerasConfigurationException Invalid Keras configuration
  @see org.deeplearning4j.nn.conf.InputPreProcessor