code: def handle_save(self, request, response):
          
          form_valid = isinstance(response, HttpResponseRedirect)
          if request.POST.get("_save") and form_valid:
              return redirect("admin:index")
          return response
docs: Handles redirect back to the dashboard when save is clicked
          (eg not save and continue editing), by checking for a redirect
          response, which only occurs if the form is valid.