4chan thread image downloader

from bs4 import BeautifulSoup
import urllib2
import os

url = raw_input('Thread URL: ')
subfolder = raw_input('Subfolder name: ')
if len(subfolder) > 0:
    path = os.path.abspath('./4chdl/' + subfolder)
elif len(subfolder) == 0:
    path = os.path.abspath('./4chdl')
if not os.path.exists(path):
    os.makedirs(path)

page = BeautifulSoup(urllib2.urlopen(url))
for link in page.findAll('a', attrs = {'class' : 'fileThumb'}):
    href = 'http://' + link['href'][2:]
    res = urllib2.urlopen(href)
    data = res.read()
    name = href[-17:]
    filename = os.path.join(path, name)
    if os.path.exists(filename):
        print '%s already exists.' % name
    else:
        f = open(filename, 'wb')
        f.write(data)
        f.close()
        print '%s downloaded' % name