Function spawn_encoder_sink_bounded 

pub fn spawn_encoder_sink_bounded<I, E, N>(
    encoder: N,
    buffer_size: usize,
) -> Sender<I>
where
    I: Send + 'static,
    E: From<Error> + Debug + 'static,
    N: Encoder<Item = I, Error = E> + Send + 'static,

Spawn a new thread that encodes each item and writes it to stdout. The channel to send items to the spawned thread is bounded in size.