+
−class LazyUser(object):
+
−    def __get__(self, request, obj_type=None):
+
−        if not hasattr(request, '_cached_user'):
+
−            from django.contrib.auth import get_user
+
−            request._cached_user = get_user(request)
+
−        return request._cached_user
+
−
+
−class AuthenticationMiddleware(object):
+
−    def process_request(self, request):
+
−        assert hasattr(request, 'session'), "The Django authentication middleware requires session middleware to be installed. Edit your MIDDLEWARE_CLASSES setting to insert 'django.contrib.sessions.middleware.SessionMiddleware'."
+
−        request.__class__.user = LazyUser()
+
−        return None