[1.6.x] Fixed typo in docs/ref/contrib/admin/index.txt.

    filtering based on add, change, and delete permissions::

        class MyModelAdmin(admin.ModelAdmin):

            def get_inline_instances(request, obj=None):

            def get_inline_instances(self, request, obj=None):

                return [inline(self.model, self.admin_site) for inline in self.inlines]

.. method:: ModelAdmin.get_urls()