Slugify tags in an html document

slugger.py

import re
import sys
from BeautifulSoup import BeautifulSoup
from slugify import slugify


def fix_tags(attr):
    return ','.join(slugify(t) for t in re.split(r',+', attr))

soup = BeautifulSoup(open(sys.argv[1]))
for link in soup.findAll('a'):
    if 'tags' in dict(link.attrs):
        link['tags'] = fix_tags(link['tags'])

print soup