boto - 从冰川下载

Question

我可以将文件上传到冰川保险库。但是如何下载文件？

import boto
ACCESS_KEY_ID = "abc"
SECRET_ACCESS_KEY = "pqr" 
glacier_connection = boto.connect_glacier(aws_access_key_id=ACCESS_KEY_ID, aws_secret_access_key=SECRET_ACCESS_KEY)

vault = glacier_connection.create_vault("backup")
archive_id=vault.upload_archive("aws.sh")

我预计以下代码会从冰川下载文件。但它不起作用。

retrieve_job=vault.retrieve_archive(archive_id)
if retrieve_job.completed:
    retrieve_job.download_to_file("test.pl")