pub trait Dummy<T>: Sized {
    fn dummy_with_rng<R: Rng + ?Sized>(config: &T, rng: &mut R) -> Self;
    fn dummy(config: &T) -> Self { ... }
}pub trait Dummy<T>: Sized {
    fn dummy_with_rng<R: Rng + ?Sized>(config: &T, rng: &mut R) -> Self;
    fn dummy(config: &T) -> Self { ... }
}