pub fn send_async<'s, 'r>(
            &'s mut self,
            addr: &'r [u8; 6],
            data: &'r [u8],
        ) -> SendFuture<'s, 'r> {
            SendFuture {
                _sender: PhantomData,
                addr,
                data,
                sent: false,
            }
        }
Sends data asynchronously to a peer (using its MAC) using ESP-NOW.
esp-wifi/src/esp_now/mod.rs