def page_not_found(request, template_name='404.html'):
"""
404 (page not found) handler which uses Jinja2 to render the template.
The default template is ``404.html``, and its context will contain
``request_path`` (the path of the requested URL) and any additional
parameters provided by the registered context processors (this view uses
``RequestContext``).
"""
context = RequestContext(request, {'request_path': request.path})
response = context.render_response(template_name)
response.status_code = 404
return response
