Macro nn 

nn!() { /* proc-macro */ }

nn! is a procedural macro designed to streamline the process of creating new neural networks;

nn! {
    MyNeuralNetwork {
        layout: { input: 128, output: 10 },
        params: {
            learning_rate: 0.01,
            epochs: 100,
            ...
       },
        layers: [Linear, ReLU, ..., Linear],
    }     
}