nautilus3, метаданные

import os
import urllib
import nautilus
from mutagen.easyid3 import EasyID3
from mutagen.mp3 import MPEGInfo

class ColumnExtension(nautilus.ColumnProvider, nautilus.InfoProvider):
        def __init__(self):
                pass

        def get_columns(self):
                return (nautilus.Column("NautilusPython::title_column",
                                "title",
                                "Title",
                                "Song title"),
                nautilus.Column("NautilusPython::album_column",
                                "album",
                                "Album",
                                "Album"),
                nautilus.Column("NautilusPython::artist_column",
                                "artist",
                                "Artist",
                                "Artist"),
                nautilus.Column("NautilusPython::bitrate_column",
                                "bitrate",
                                "Bitrate",
                                "Bitrate"),)

        def update_file_info(self, file):
                if file.get_uri_scheme() != 'file':
                        return
                if file.is_mime_type('audio/mpeg'):
                        filename = urllib.unquote(file.get_uri()[7:])
                        audio = EasyID3(filename)

                if (os.path.isfile (filename)):
                        mpfile = open (filename)
                        mpinfo = MPEGInfo (mpfile)
                        br = str(mpinfo.bitrate/1000) + " Kbps"
                else:
                        br = ""

                file.add_string_attribute('title', audio["title"][0])
                file.add_string_attribute('album', audio["album"][0])
                file.add_string_attribute('artist', audio["artist"][0])
                file.add_string_attribute('bitrate', br)
                self.get_columns()