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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 GetNotificationShard(self, queue):
 """Gets a single shard for a given queue."""

    queue_name = str(queue)
    QueueManager.notification_shard_counters.setdefault(queue_name, 0)
    QueueManager.notification_shard_counters[queue_name] += 1
    notification_shard_index = (
        QueueManager.notification_shard_counters[queue_name] %
        self.num_notification_shards)
    if notification_shard_index > 0:
      return queue.Add(str(notification_shard_index))
    else:
      return queue