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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_pwm_values(self, brightness=None, color=None):
 """ Get the pwm values for a specific state of the led. If a state argument is omitted, current value is used. :param brightness: The brightness of the state. :param color: The color of the state. :return: The pwm values. """

        if brightness is None:
            brightness = self.brightness
        if color is None:
            color = self.color

        return [(x / 255) * brightness for x in self._rgb_to_rgbw(color)]