Turn the button lights on then off in a snakelike sequence.
        NOTE! Does not remember prior state of lights and will finish
        with all lights off.
        :param duration: The duration to hold each individual button.

def snake(self, duration: float = 0.03):
        """
        Turn the button lights on then off in a snakelike sequence.
        NOTE! Does not remember prior state of lights and will finish
        with all lights off.
        :param duration: The duration to hold each individual button.
        """
        for button in BUTTONS:
            self.light_on(button)
            time.sleep(duration)

        for button in reversed(BUTTONS):
            self.light_off(button)
            time.sleep(duration)