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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 recv(self):
 """Receive message from the backend or wait unilt next message."""

        try:
            message = self.ws.recv()
            return json.loads(message)
        except websocket._exceptions.WebSocketConnectionClosedException as ex:
            raise SelenolWebSocketClosedException() from ex