目录方法1：（永久更改）方法2：（永久更改）方法3：（临时性使用）备注：pip下载源常用的国内镜像如下：总结 方法1：（永久更改）
I have several \'select\' elements on the page. When I choose some ofoptions, the ajax request is being sent to server and the element adjacent to this \'select\' must be updated with response value.
加载中,请稍侯......