Python script for minifying CSS?

import sys, re

css = open( sys.argv[1] , 'r' ).read()

# remove comments - this will break a lot of hacks :-P
css = re.sub( r's*/*s**/', "$$HACK1$$", css ) # preserve IE<6 comment hack
css = re.sub( r'/*[sS]*?*/', "", css )
css = css.replace( "$$HACK1$$", '/**/' ) # preserve IE<6 comment hack

# url() doesn't need quotes
css = re.sub( r'url((["'])([^)]*)1)', r'url(2)', css )

# spaces may be safely collapsed as generated content will collapse them anyway
css = re.sub( r's+', ' ', css )

# shorten collapsable colors: #aabbcc to #abc
css = re.sub( r'#([0-9a-f])1([0-9a-f])2([0-9a-f])3(s|;)', r'#1234', css )

# fragment values can loose zeros
css = re.sub( r':s*0(.d+([cm]m|e[mx]|in|p[ctx]))s*;', r':1;', css )

for rule in re.findall( r'([^{]+){([^}]*)}', css ):

    # we don't need spaces around operators
    selectors = [re.sub( r'(?<=[[(>+=])s+|s+(?=[=~^$*|>+])])', r'', selector.strip() ) for selector in rule[0].split( ',' )]

    # order is important, but we still want to discard repetitions
    properties = {}
    porder = []
    for prop in re.findall( '(.*?):(.*?)(;|$)', rule[1] ):
        key = prop[0].strip().lower()
        if key not in porder: porder.append( key )
        properties[ key ] = prop[1].strip()

    # output rule if it contains any declarations
    if properties:
        print "%s{%s}" % ( ','.join( selectors ), ''.join(['%s:%s;' % (key, properties[key]) for key in porder])[:-1] )