pub trait SubscribeExt<M>{
// Required method
fn subscribe<'life0, 'async_trait>(
&'life0 self,
broker: Address<Broker<M>>,
) -> Pin<Box<dyn Future<Output = Result<Subscription<M>, ()>> + Send + 'async_trait>>
where Self: 'async_trait,
'life0: 'async_trait;
}