code: func (b *LEDDriver) UpRightArrow() (err error) {
  	buf := []byte{0x0F, 0x03, 0x05, 0x09, 0x10}
  	err = b.WriteMatrix(buf)
  	return
  }
docs: // UpRightArrow displays an arrow pointing upwards and to the right on the Microbit LEDs