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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_config_value(self, key, value):
 """Sets a value for a room config"""


        self.check_owner()
        params = {"room": self.room_id, "config": to_json({key: value})}
        resp = self.conn.make_api_call("setRoomConfig", params)
        if "error" in resp:
            raise RuntimeError(f"{resp['error'].get('message') or resp['error']}")
        return resp