Add docs for `response_add`, `response_change` and `response_delete`

    Returns an instance of the paginator to use for this view. By default,

    instantiates an instance of :attr:`paginator`.

.. method:: ModelAdmin.response_add(self, request, obj, post_url_continue=None)

    Determines the HttpResponse for the add_view stage.

    ``response_add`` is called after the admin form is submitted and

    just after the object and all the related instances have

    been created and saved. You can override it to change the default behavior

    after the object has been created.

.. method:: ModelAdmin.response_change(self, request, obj)

    Determines the HttpResponse for the change_view stage.

    ``response_change`` is called after the admin form is submitted and

    just after the object and all the related instances have

    been saved. You can override it to change the default

    behavior after the object has been changedn.

.. method:: ModelAdmin.response_delete(self, request, obj_display)

    Determines the HttpResponse for the delete_view stage.

    ``response_delete`` is called after the object has been

    deleted. You can override it to change the default

    behavior after the object has been deleted.

    ``obj_display`` is a string with the name of the deleted

    object.

Other methods

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