Fixed #10898 -- Corrected minor error in conditional view processing example....

The two functions, to compute the ETag and the last modified time, will be

passed the incoming ``request`` object and the same parameters, in the same

order, as the view function they are helping to wrap. The function passed

``last_modified`` should return a standard datetime value specifying the last

time the resource was modified, or ``None`` if the resource doesn't exist. The

function passed to the ``etag`` decorator should return a string representing

the `Etag`_ for the resource, or ``None`` if it doesn't exist.

``last_modified_func`` should return a standard datetime value specifying the

last time the resource was modified, or ``None`` if the resource doesn't

exist. The function passed to the ``etag`` decorator should return a string

representing the `Etag`_ for the resource, or ``None`` if it doesn't exist.

Using this feature usefully is probably best explained with an example.

Suppose you have this pair of models, representing a simple blog system::

need the latest ``published`` date for every entry associated with that blog.

One way to do this would be::

    from django.db.models import Max

    def latest_entry(request, blog_id):

        return Entry.objects.filter(blog=blog_id).aggregate(Max("published"))

        return Entry.objects.filter(blog=blog_id).latest("published").published

You can then use this function to provide early detection of an unchanged page

for your front page view::