python - Django can't find my custom template filter -

i'm trying create custom template filter in django app. i've created templatetags folder under app, added __init__.py file , filters.py file filters, so:

import os django import template django.template.defaultfilters import stringfilter  register = template.library()  @register.filter @stringfilter def filename(pathname):     """ returns file's name, without folder """     return os.path.basename(pathname) 

when try access filter template, error "invalid filter 'filename'"

this question has been asked lot, checked following:

• __init__.py named
• after opening shell manage.py shell can import filter so: import app.templatetags
• i can use filter django shell
• i have restarted django development server.
• i have placed breakpoint on call template.library() - debugger doesn't stop there.

here template (i've removed parts of it, error persists in small version, well)

<form enctype="multipart/form-data" action="{% url lab.views.new.artefact_drop_web tempfile_id=tempfile.id %}" method="post">      {% csrf_token %}      <h3>file:</h3>     <p>{{ tempfile.file.name|filename }}</p>     <input type="submit" value="add" /> </form> 

you need use {% load name_of_file_tags_are_in %} inside template.

https://docs.djangoproject.com/en/1.5/howto/custom-template-tags/