Django multi-model update in Admin?

How can I select multiple items from an admin view and create a custom action?

Scenario: We need to select a set of books and assign开发者_开发问答 set of categories (from a list) and assign them to them.

Is it possible to achieve this in Django Admin?

Thanks.

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already included in django: http://docs.djangoproject.com/en/dev/ref/contrib/admin/actions/

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We ended up doing a custom view and works fine.