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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 _create_shade_data(self, position_data=None, room_id=None):
 """Create a shade data object to be sent to the hub"""

        base = {ATTR_SHADE: {ATTR_ID: self.id}}
        if position_data:
            base[ATTR_SHADE][ATTR_POSITION_DATA] = position_data
        if room_id:
            base[ATTR_SHADE][ATTR_ROOM_ID] = room_id
        return base