pub trait FnMutOneArg<Arg> {
type FnOutput;
// Required method
fn call_mut_with_one_arg(&mut self, arg: Arg) -> Self::FnOutput;
}
pub trait FnMutOneArg<Arg> {
type FnOutput;
// Required method
fn call_mut_with_one_arg(&mut self, arg: Arg) -> Self::FnOutput;
}