wget http://ftp.sjtu.edu.cn/html/help/debian/stable/sources.list
file content:
#deb http://ftp.sjtu.edu.cn/debian/ stable main
deb http://ftp.sjtu.edu.cn/debian stable main contrib non-free
deb-src http://ftp.sjtu.edu.cn/debian stable main
deb http://ftp.sjtu.edu.cn/debian-security stable/updates main
# deb http://security.debian.org/ stable/updates main