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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 saturation(self, saturation):
 """ Set the group saturation. :param saturation: Saturation in decimal percent (0.0-1.0). """

        if saturation < 0 or saturation > 1:
            raise ValueError("Saturation must be a percentage "
                             "represented as decimal 0-1.0")
        self._saturation = saturation
        self._update_color()
        if saturation == 0:
            self.white()
        else:
            cmd = self.command_set.saturation(saturation)
            self.send(cmd)