docs: def update_links(self, request, admin_site=None):
          """
          Called to update the widget's urls. Tries to find the
          bundle for the model that this foreign key points to and then
          asks it for the urls for adding and listing and sets them on
          this widget instance. The urls are only set if request.user
          has permissions on that url.
  
          :param request: The request for which this widget is being rendered.
          :param admin_site: If provided, the `admin_site` is used to lookup \
          the bundle that is registered as the primary url for the model \
          that this foreign key points to.
          """
          if admin_site:
              bundle = admin_site.get_bundle_for_model(self.model.to)
  
              if bundle:
                  self._api_link = self._get_bundle_link(bundle, self.view,
                                                         request.user)
                  self._add_link = self._get_bundle_link(bundle, self.add_view,
                                                         request.user)