convert youtube url for iframe, js api

@register.assignment_tag
def get_video_urls(obj, attr_name=None):
    """
    {% get_video_urls url as url_object %} or \

    get object attribute
    {% get_video_urls obj "url" as url_object %}

    {{ url_object }} original url
    {{ url_object.video_id }} original url or video_id
    {{ url_object.resource }} youtube, vimeo, None
    {{ url_object.iframe_url }} original url or iframe_url
    {{ url_object.js_api_url }} original url or js_api_url
    """
    if not isinstance(obj, basestring):
        url = getattr(obj, attr_name)
    elif not attr_name:
        url = obj
    else:
        raise AttributeError

    class VideoId(str):
        def __new__(cls, *args, **kwargs):
            video_id, resource = args
            new_class = str.__new__(cls, video_id)
            new_class.resource = resource
            new_class.video_id = video_id

            if resource == 'youtube':
                new_class.iframe_url = 'http://www.youtube.com/embed/%s' % video_id
                new_class.js_api_url = 'http://www.youtube.com/watch?v=%s' % video_id
            elif resource == 'vimeo':
                new_class.iframe_url = 'http://player.vimeo.com/video/%s' % video_id
                new_class.js_api_url = 'http://player.vimeo.com/video/%s?api=1&player_id=vimeoplayer' % video_id
            else:
                new_class.iframe_url = video_id
                new_class.js_api_url = video_id
            return new_class

    def __repl(m):
        repl = m.groupdict()
        result = ''
        if repl.has_key('video_youtube_id'):
            result = repl['video_youtube_id'] + '__and__' + 'youtube'
        elif repl.has_key('video_vimeo_id'):
            result = repl['video_vimeo_id'] + '__and__' + 'vimeo'
        return result

    result = None
    matches = None
    if url:
        rs = [re.compile(r"^https?\:\/\/(www\.)?youtu\.be\/(?P<video_youtube_id>[^\/]*)\??.*$"),
             re.compile(r"^https?\:\/\/(www\.)?youtube\.(com|nl|ru).*v=(?P<video_youtube_id>.*)\&?.*$"),
             re.compile(r"^https?\:\/\/(www\.)?youtube\.(com|nl|ru)\/embed\/(?P<video_youtube_id>[^\/]*)\??.*$"),
             re.compile(r"^https?\:\/\/(www\.)?vimeo\.com\/(?P<video_vimeo_id>[^\/]*)\??.*$"),]
        for r in rs:
            result, matches = r.subn(__repl, url)
            if matches:
                return VideoId(*result.split('__and__'))
        if not matches:
            return VideoId(result)
    return result