今天晚上修改了软件源，下载了一些软件，然后又改了回来，可是再使用apt-get命令更新时一直会报如下错误：W: 无法下载 http://packages.linuxdeepin.com/deepin/ ... /InRelease  Unable to find expected entry 'restricted/source/Sources' in Release file (Wrong sources.list entry or malformed file)

E: Some index files failed to download. They have been ignored, or old ones used instead.
请问一下，这个问题该如何解决，谢谢！