how to load 2 cppflow models in memory and make inference with auto prediction = (*model)(input)

Question

I would like to know how to load two models in memory and make inference with model1 or model2 like I want?

int __stdcall BinaCpp_loadNN(const char* filename)
{
    //loading the model each time causes overload. 
    //The other option is to create a unique pointer which will be loaded once when first called.

    //Declare unique pointer:

    std::unique_ptr<cppflow::model> model;

    model = std::make_unique<cppflow::model>(filename);

    return model;  //issue here
}