Flickr Set Downloader

#!/usr/bin/python
import flickrapi
import urllib2
from optparse import OptionParser
import sys


api_key  =  'THISISANAPIKEY' #get your own!
userID='00000000@N06' #This is a user ID, you'll want to use your own
setID=''

parser = OptionParser()
parser.add_option ("-s","--setid",type="string",dest="setID",help="The Set ID for the set to download.")
parser.add_option ("-S" , "--size", type="string", dest="photoSize",default="b",help="The size of photo you want to download. Size must fit the following: s - 75x75, q - 150x150, t - 100 on the longest side, m - 240 on the longest side, n - 320 on the longest side, z - 640 on the longest side, c - 800 on the longest side, \nb - 1024 on the longest side (default), o - original")

(options, args) = parser.parse_args()

setID = options.setID
photoSize = options.photoSize

if options.setID is None:
    print "You must specify a photo set to download. \nSee python-download -h for examples."
    sys.exit()

flickr = flickrapi.FlickrAPI(api_key)
photoSet = flickr.photosets_getPhotos(photoset_id=setID)
photoSet = photoSet[0]

def download( url ):
    file_name = url.split('/')[-1]
    u = urllib2.urlopen(url)
    f = open(file_name, 'wb')
    meta = u.info()
    file_size = int(meta.getheaders("Content-Length")[0])
    print "Downloading: %s Bytes: %s" % (file_name, file_size)

    file_size_dl = 0
    block_sz = 8192
    while True:
        buffer = u.read(block_sz)
        if not buffer:
        break

        file_size_dl += len(buffer)
        f.write(buffer)
        status = r"%10d  [%3.2f%%]" % (file_size_dl, file_size_dl * 100. / file_size)
        status = status + chr(8)*(len(status)+1)
        print status,

    f.close()
    return

for photo in photoSet:
    photoID = photo.attrib['id']
    photoInfo = flickr.photos_getInfo(photo_id=photoID)
    photoInfo = photoInfo[0]
    secret=photoInfo.attrib['secret']
    oSecret=photoInfo.attrib['originalsecret']

    if photoSize == "o":
        download("http://farm%s.static.flickr.com/%s/%s_%s_o.jpg" % (photo.attrib['farm'], photo.attrib['server'], photo.attrib['id'],oSecret))
    else:
        download("http://farm%s.static.flickr.com/%s/%s_%s_%s.jpg" % (photo.attrib['farm'], photo.attrib['server'], photo.attrib['id'],secret,photoSize))