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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 purge_old_event_logs(delete_before_days=7):
 """ Purges old event logs from the database table """

    delete_before_date = timezone.now() - timedelta(days=delete_before_days)
    logs_deleted = EventLog.objects.filter(
        created_on__lte=delete_before_date).delete()
    return logs_deleted