pub fn clone_box<T>(t: &T) -> Box<T>Notable traits for Box<I, A>impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<F, A> Future for Box<F, A> where
    F: Future + Unpin + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;
where
    T: ?Sized + DynClone