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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 websocket_connect(self, message):
 """Called when WebSocket connection is established."""

        self.session_id = self.scope['url_route']['kwargs']['subscriber_id']
        super().websocket_connect(message)

        # Create new subscriber object.
        Subscriber.objects.get_or_create(session_id=self.session_id)