code: private ModelDescriptor getModelDescriptor(Model model, File modelFile) throws FOSException {
          if (model instanceof ModelBinary) {
              return new ModelDescriptor(ModelDescriptor.Format.BINARY, modelFile.getAbsolutePath());
          } else if (model instanceof ModelPMML) {
              return new ModelDescriptor(ModelDescriptor.Format.PMML, modelFile.getAbsolutePath());
          } else {
              throw new FOSException("Unsupported Model type '" + model.getClass().getSimpleName() + "'.");
          }
      }
docs: Returns a new {@link com.feedzai.fos.api.ModelDescriptor} for the given {@code model} and {@code file}.
  
  @param model     The {@link Model} with the classifier.
  @param modelFile The file where the model will be saved.
  @return          A new {@link com.feedzai.fos.api.ModelDescriptor}
  @throws FOSException If the given {@code model} is of an unknown instance.