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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 set_slats_level(self, slatsLevel=0.0, shutterLevel=None):
 """ sets the slats and shutter level Args: slatsLevel(float):
 the new level of the slats. 0.0 = open, 1.0 = closed, shutterLevel(float):
 the new level of the shutter. 0.0 = open, 1.0 = closed, None = use the current value Returns: the result of the _restCall """

        if shutterLevel is None:
            shutterLevel = self.shutterLevel
        data = {
            "channelIndex": 1,
            "deviceId": self.id,
            "slatsLevel": slatsLevel,
            "shutterLevel": shutterLevel,
        }
        return self._restCall("device/control/setSlatsLevel", json.dumps(data))