Rust equivalent to Swift’s extension methods to a protocol?

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In Rust, you can use extension traits, that is a trait with a generic implementation for all types T that implement the base trait:

struct Kaz {}

impl Foo for Kaz {}

trait Foo {
    fn sample1(&self) -> isize { 111 } 
}

trait FooExt {
    fn sample2(&self);
}

impl<T: Foo> FooExt for T {
    fn sample2(&self) {
        println!("{}", self.sample1());
    }
}

fn main() {
    let x = Kaz {};
    x.sample1();
    x.sample2();
}

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