Typo in 'Raising 404' listing

[anonymous]

in the 'Raising 404' listing there is a simple typo:
Http404 is a function that's why line 7 should be

raise Http404()

and not raise Http404

[Aymeric Augustin]

Http404 is not a function; it's a class and it inherits Exception.

Python allows raising exceptions like this: ​http://docs.python.org/tutorial/errors.html#raising-exceptions

The sole argument to raise indicates the exception to be raised. This must be either an exception instance or an exception class (a class that derives from Exception).

A grep over the source and docs shows that both kinds or raise (with a class or an instance) are commonly used.