gistfile1.txt

keys = ['job_2254-t02240.pdf',
'job_2254-t02240.pdf',
'job_2254-t02244.pdf',
'job_2254-t02241.pdf',
'job_2254-t02242.pdf',
'job_2254-t02293.pdf',
'job_2254-t02243.pdf',
'job_2254-t0220.pdf',
'job_2254-t0221.pdf',
'job_2254-t0222.pdf',
'job_2254-t0000016.pdf',
'smsprime.pdf',

]

for keystr in keys:
    key = bucket.lookup(keystr)
    print key.content_type
    print key.content_disposition
    key.copy(key.bucket, key.name, preserve_acl=True, metadata={'Content-Type': 'application/octet-stream', 
                                                                'Content-Disposition' : 'attachment'})