retag.py

from mutagen.easyid3 import EasyID3 as Tag
from os import listdir
from re import sub

for f in listdir('.'):
    if (f[-4:] == '.mp3'):
        try:
            tag = Tag(f)
        except:
            tag = Tag()
        tag['artist'] = 'Steve Miller Band'
        tag['album'] = 'Brave New World'
        tag['date'] = '1969'
        tag['genre'] = 'Rock & Roll'
        tag['tracknumber'] = '%02d/%02d' % (int(f[:2]), 9)
        # tag['discnumber'] = '%02d/%02d' % (2, 2)
        tag['title'] = f[3:-4]
        tag.save(f)