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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 onOpen(self):
 """ Called when a client has opened a websocket connection """

        self.factory.add_client(self)

        # Publish ON_OPEN message
        self.factory.mease.publisher.publish(
            message_type=ON_OPEN, client_id=self._client_id, client_storage=self.storage)