Options in Rust

fn work_experience(occupation: &str) -> Option<u32>{
  match occupation{
    "Junior Developer" => Some(5),
    "Senior Developer" => Some(10),
    "Project Manager" => Some(15),
    _ => None
  }
}
fn main() {
  println!("Years of work experience for a junior developer: {}", match work_experience("Junior Developer"){
    Some(opt) => format!("{} years", opt),
    None => "0 years".to_string()
  });
  println!("\nYears of work experience for a student: {}", match work_experience("Student"){
    Some(opt) => format!("{} years", opt),
    None => "0 years".to_string()
  });
}