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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:
 async def get_protocol_version(self):
 """ This method retrieves the Firmata protocol version. JSON command: {"method": "get_protocol_version", "params": ["null"]} :returns: {"method": "protocol_version_reply", "params": [PROTOCOL_VERSION]} """

        value = await self.core.get_protocol_version()
        if value:
            reply = json.dumps({"method": "protocol_version_reply", "params": value})
        else:
            reply = json.dumps({"method": "protocol_version_reply", "params": "Unknown"})
        await self.websocket.send(reply)