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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 target_heating_level(self):
 """Return target heating level."""

        try:
            if self.side == 'left':
                level = self.device.device_data['leftTargetHeatingLevel']
            elif self.side == 'right':
                level = self.device.device_data['rightTargetHeatingLevel']
            return level
        except TypeError:
            return None