pub trait Handler<Input, Output, Metadata>: Send{
// Required method
fn exec<'life0, 'life1, 'async_trait>(
&'life0 self,
exchange: &'life1 mut Exchange<Input, Output, Metadata>,
) -> Pin<Box<dyn Future<Output = Result<HandlerStatus, HandlerExecutionError>> + Send + 'async_trait>>
where Self: 'async_trait,
'life0: 'async_trait,
'life1: 'async_trait;
}