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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 motion_sensor(self, enabled):
 """Set the motion sensor state."""

        if enabled is True:
            value = CONST.SETTINGS_MOTION_POLICY_ON
        elif enabled is False:
            value = CONST.SETTINGS_MOTION_POLICY_OFF
        else:
            raise SkybellException(ERROR.INVALID_SETTING_VALUE,
                                   (CONST.SETTINGS_MOTION_POLICY, enabled))

        self._set_setting({CONST.SETTINGS_MOTION_POLICY: value})