install sustemtap on ubuntu failed

[Timo Juhani Lindfors]

Hatt Tom <net.study.sea@gmail.com> writes:
>      sh>  cat /etc/apt/sources.list.d/ddebs.list
>      cat: /etc/apt/sources.list.d/ddebs.list: No such file or
>      directory

Ok, then how did you install linux-image-3.5.0-23-generic-dbgsym?