Internet Explorer detection

ie.py

def is_ie(request, min_version=None, max_version=None): 
    user_agent = request.environ.get('HTTP_USER_AGENT', '') 
    ie = user_agent.find('MSIE') 
    if ie==-1: 
        return False 
 
    if not min_version and not max_version: 
        return True 
 
    version_match = re.match('[\d\.]*', user_agent[ie+5:]) 
    if not version_match: 
        return False 
 
    version = tuple(map(int, version_match.group(0).split('.'))) 
    result = True 
 
    if min_version: 
        result = result and version >= min_version 
 
    if max_version: 
        result = result and version <= max_version 
 
    return result