django 'thumbnail' ist kein Gültiger tag-Bibliothek:

Habe ich versucht django-filer auswählen, mehrere Dateien in einer einzigen filefield nur ich habe versucht, für mein einfaches Modell, und ich ma vor diesem template-Fehler. ich habe gerade verwendet ein einfaches Modell im django admin.
könnten Sie mir bitte helfen?

class MyFile(models.Model):
     title = models.CharField(max_length=200)
     cover = FilerFileField(null=True,blank=True)


Environment:


 Request Method: GET
 Request URL: http://127.0.0.1:8000/filer/folder/?t=id&pop=1

 Django Version: 1.3.1
 Python Version: 2.6.5
 Installed Applications:
 ['django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.sites',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'django.contrib.admin',
 'filer',
 'intelligence_centre']
  Installed Middleware:
  ('django.middleware.common.CommonMiddleware',
  'django.contrib.sessions.middleware.SessionMiddleware',
   'django.middleware.csrf.CsrfViewMiddleware',
   'django.contrib.auth.middleware.AuthenticationMiddleware',
   'django.contrib.messages.middleware.MessageMiddleware')


  Template error:
    In template /usr/local/lib/python2.6/dist-packages/filer/templates/admin/filer/tools/clipboard/clipboard.html, error at line 1
     'thumbnail' is not a valid tag library: Template library thumbnail not found, tried django.templatetags.thumbnail,django.contrib.admin.templatetags.thumbnail,filer.templatetags.thumbnail
      1 :  {% load thumbnail i18n %} 


  2 : {% for clipboard in user.filer_clipboards.all %}


  3 : <table style="width: 100%; border: 1px solid #DDDDDD;" class="clipboard">


  4 :     <thead>


  5 :         <tr><th colspan="3">{% trans "Clipboard" %}</th></tr>


  6 :     </thead>


  7 :     <tfoot>


  8 :         <tr>


  9 :             <td colspan="3">


         10 :                 <form action="{% url admin:filer-paste_clipboard_to_folder %}" method="post" style="display: inline;">


        11 :                     {% csrf_token %}

---

Traceback: 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/core/handlers/base.py" in get_response 
111. Antwort = callback(Anfrage, *callback_args, **callback_kwargs) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/utils/decorators.py" in _wrapped_view 
93. Antwort = view_func(Anfrage, *args, **kwargs) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/views/decorators/cache.py" in _wrapped_view_func 
79. Antwort = view_func(Anfrage, *args, **kwargs) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/contrib/admin/sites.py" im inneren 
197. return view(request, *args, **kwargs) 
Datei "/usr/local/lib/python2.6/dist-packages/filer/admin/folderadmin.py" in directory_listing 
241. }, context_instance=RequestContext(request)) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/shortcuts/__init__.py" in render_to_response 
20. return HttpResponse(loader.render_to_string(*args, **kwargs), **httpresponse_kwargs) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in render_to_string 
181. t = get_template(template_name) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in get_template 
157. Vorlage, origin = find_template(template_name) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in find_template 
134. Quelle, display_name = loader(name, Verzeichnisse) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in __call__ 
42. return self.load_template(template_name, template_dirs) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in load_template 
48. template = get_template_from_string(Quelle, Ursprung, template_name) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in get_template_from_string 
168. return Template(Quelle, Ursprung, name) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in __init__ 
108. selbst.nodelist = compile_string(template_string, Herkunft) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in compile_string 
136. return parser.parse() 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in parse 
239. compiled_result = compile_func(self, token) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader_tags.py" in do_extends 
214. nodelist = parser.parse() 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in parse 
239. compiled_result = compile_func(self, token) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader_tags.py" in do_block 
192. nodelist = parser.parse(('endblock', 'endblock %s' % block_name)) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in parse 
239. compiled_result = compile_func(self, token) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader_tags.py" in do_include 
261. isolated_context=isolated_context) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader_tags.py" in __init__ 
149. t = get_template(template_path) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in get_template 
157. Vorlage, origin = find_template(template_name) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in find_template 
134. Quelle, display_name = loader(name, Verzeichnisse) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in __call__ 
42. return self.load_template(template_name, template_dirs) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in load_template 
48. template = get_template_from_string(Quelle, Ursprung, template_name) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/loader.py" in get_template_from_string 
168. return Template(Quelle, Ursprung, name) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in __init__ 
108. selbst.nodelist = compile_string(template_string, Herkunft) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in compile_string 
136. return parser.parse() 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/base.py" in parse 
239. compiled_result = compile_func(self, token) 
Datei "/work/ws/intcen/venv/lib/python2.6/site-packages/django/template/defaulttags.py" im laden 
1054. (taglib, e)) 

Der Ausnahme-Typ: TemplateSyntaxError in /filer/Ordner/
Ausnahme Wert: 'thumbnail' ist kein Gültiger tag-Bibliothek: Template library thumbnail nicht gefunden, versucht django.templatetags.Miniatur,django.contrib.admin.templatetags.thumbnail-filer.templatetags.Miniatur 

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