Assuming `"abc".parse::<i32>()` returns an Err, what happens when this function runs?
fn parse_and_double(s: &str) -> Result<i32, std::num::ParseIntError> {
let n = s.parse::<i32>()?;
Ok(n * 2)
}
fn main() {
let r = parse_and_double("abc");
println!("{:?}", r);
}