A Middleware that can be applied to your views to turn ObjectDoesNotExist exceptions into Http404 exceptions. This means people will see a "Page not found" error rather than an "Internal Server Error" when they are request something that does not exist in the database.

DoesNotExistTo404.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from django.core.exceptions import ObjectDoesNotExist
from django.http import Http404

class DoesNotExistTo404Middleware(object):
    def process_exception(self, request, exception):
        if isinstance(exception,ObjectDoesNotExist):
            raise Http404(exception.message)