def response_change(self, request, obj):
        """
        Determines the HttpResponse for the change_view stage.
        """

        if IS_POPUP_VAR in request.POST:
            to_field = request.POST.get(TO_FIELD_VAR)
            attr = str(to_field) if to_field else obj._meta.pk.attname
            # Retrieve the `object_id` from the resolved pattern arguments.
            value = request.resolver_match.args[0]
            new_value = obj.serializable_value(attr)
            popup_response_data = json.dumps({
                'action': 'change',
                'value': six.text_type(value),
                'obj': six.text_type(obj),
                'new_value': six.text_type(new_value),
            })
            return SimpleTemplateResponse('admin/popup_response.html', {
                'popup_response_data': popup_response_data,
            })

        opts = self.model._meta
        pk_value = obj._get_pk_val()
        preserved_filters = self.get_preserved_filters(request)

        msg_dict = {
            'name': force_text(opts.verbose_name),
            'obj': format_html('<a href="{}">{}</a>', urlquote(request.path), obj),
        }
        if "_continue" in request.POST:
            msg = format_html(
                _('The {name} "{obj}" was changed successfully. You may edit it again below.'),
                **msg_dict
            )
            self.message_user(request, msg, messages.SUCCESS)
            redirect_url = request.path
            redirect_url = add_preserved_filters({'preserved_filters': preserved_filters, 'opts': opts}, redirect_url)
            return HttpResponseRedirect(redirect_url)

        elif "_saveasnew" in request.POST:
            msg = format_html(
                _('The {name} "{obj}" was added successfully. You may edit it again below.'),
                **msg_dict
            )
            self.message_user(request, msg, messages.SUCCESS)
            redirect_url = reverse('admin:%s_%s_change' %
                                   (opts.app_label, opts.model_name),
                                   args=(pk_value,),
                                   current_app=self.admin_site.name)
            redirect_url = add_preserved_filters({'preserved_filters': preserved_filters, 'opts': opts}, redirect_url)
            return HttpResponseRedirect(redirect_url)

        elif "_addanother" in request.POST:
            msg = format_html(
                _('The {name} "{obj}" was changed successfully. You may add another {name} below.'),
                **msg_dict
            )
            self.message_user(request, msg, messages.SUCCESS)
            redirect_url = reverse('admin:%s_%s_add' %
                                   (opts.app_label, opts.model_name),
                                   current_app=self.admin_site.name)
            redirect_url = add_preserved_filters({'preserved_filters': preserved_filters, 'opts': opts}, redirect_url)
            return HttpResponseRedirect(redirect_url)

        else:
            msg = format_html(
                _('The {name} "{obj}" was changed successfully.'),
                **msg_dict
            )
            self.message_user(request, msg, messages.SUCCESS)
            return self.response_post_save_change(request, obj)
dataset/ETHPy150Open django/django/django/contrib/admin/options.py/ModelAdmin.response_change/original