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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 remove_subscriber(session_id, observer_id):
 """Remove subscriber from the given observer. :param session_id: Subscriber's session identifier :param observer_id: Observer identifier """

    models.Observer.subscribers.through.objects.filter(
        subscriber_id=session_id, observer_id=observer_id
    ).delete()