How can I implement a trait on external struct from a package?

There is this package called eddsa that has a struct defined like this pub struct PrivateKey<E: JubjubEngine>(pub E::Fs);

I need to print a struct but I can't because it uses this package struct and doesn't have copy, clone or debug traits implemented.

How can I override, or extend the trait from this struct from an external package?

If I wrap inside another struct, still fires the error

Thanks.