Function invoke 

pub async fn invoke<P, I, O>(
    tx: O,
    rx: I,
    instance: &str,
    func: &str,
    params: impl AsRef<[u8]>,
    paths: impl AsRef<[P]> + Send,
) -> Result<(Outgoing, Incoming)>
where
    P: AsRef<[Option<usize>]> + Send + Sync,
    I: AsyncBufRead + Unpin + Send + 'static,
    O: AsyncWrite + Unpin + Send + 'static,

Invoke function func on instance instance