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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 on_open(self, ws):
 """ Callback executed when a connection is opened to the server. Handles streaming of audio to the server. :param ws: Websocket client """

        self.callback.on_connected()

        # Send initialization message
        init_data = self.build_start_message(self.options)
        self.ws_client.send(json.dumps(init_data).encode('utf8'), websocket.ABNF.OPCODE_TEXT)