Questions about `#[derive_const(...)]` and const trait impl

I've noticed recently that there is a bunch of const trait related experimental features in Rust to allow calling trait methods in const context, like const_trait_impl, const_convert, const_ops, const_cmp, const_clone, const_default, const_iter. The #[derive_const(...)] attribute works like #[derive()] but generates const trait implementations. However, when I want to extend third-party derive macros to generate const trait impls, for example the macros provided by derive_more, I don't know how...