Symlink tracks from all albums containing at least one of the top 3000 played tracks

toplink.py

import os

from django.db.models import Count
from jmc.anus.models import Track, Release
from jmc.auth import User

track_root = '../..'
jokull_root = '/web/jmc/tracks/jokull'

j = User.objects.get(username='jokull')
top_tracks = Track.objects.annotate(plays=Count('playhistory'))\
    .filter(playhistory__user=j).order_by('-plays')

release_ids = set()

def sane(filename):
    return "".join([c for c in filename if c.isalpha() or c.isdigit() or c in (' ', '-')])

def symlink(release, track):
    folder = u"[{0:04d}] {1}".format(release.date, sane(release.title))
    filename = u"{0:02d} - {1}.mp3".format(track.tracknumber or 0, sane(track.title))
    source = os.path.join(track_root, unicode(track.id))
    target = os.path.join(jokull_root, folder, filename)
    release_folder = os.path.dirname(target)
    if not os.path.exists(release_folder):
        os.mkdir(release_folder)
    try:
        os.symlink(source, target)
    except OSError, e:
        print t, e

for t in top_tracks[:3000]:
    if t.release_id is not None:
        release_ids.add(t.release_id)

for r in Release.objects.filter(id__in=list(release_ids)):
    print r.title
    for t in r.track_set.all():
        symlink(r, t)