Turn the light on for the given Button.

        NOTE! If yuo turn the "Off" button light on, the fader won't
        report value updates when it's moved.

def light_on(self, button: Button):
        """Turn the light on for the given Button.

        NOTE! If yuo turn the "Off" button light on, the fader won't
        report value updates when it's moved."""
        self.outport.send(mido.Message('polytouch', note=button.light, value=1))