btw is this how I can acquire the content ? doesn't seem to compile

```rs
        unsafe {
            // Borrow a mutable reference to the SpiDevice
            let spi_ref = SPI_INSTANCE.borrow_mut();

            // Perform the SPI transfer
            let unlock = spi_ref.get_mut();
            unlock.write(buffer).expect("SPI transfer failed");
        }```