Christian Kaula. Let the computer do it.

If you ever need to remove a cache fragment that has been created by the cache template tag do like so:

from django.core.cache import cache
from django.utils.hashcompat import md5_constructor
from django.utils.http import urlquote

def invalidate_cache_fragment(fragment_name, *args):
  cargs = md5_constructor(u':'.join([urlquote(arg) for arg in args]))
  cache_key = 'template.cache.%s.%s' % (fragment_name, cargs.hexdigest())
  cache.delete(cache_key)