djohno is a reusable Django app for ensuring your error views and templates work properly. djohno adds views which intentionally trigger HTTP 403, HTTP 404 and HTTP 500 responses. There are also views for ensuring your site email facilities are set up correctly, and for viewing versions of apps in INSTALLED_APPS and the Python version.
All djohno views are restricted to users with superuser access.
djohno also adds default 403.html, 404.html and 500.html templates, which you should override.