I think you're confused to what "systems" programming entails. User-space packaging with a bunch of scripts is not systems programming. OS installers is not systems programming.
To give you an example of what is systems programming, I have helped developed operating systems kernels, virtual machine monitors, and distributed networked systems. All of these things would be considered systems programming.
You should just read http://home.pacbell.net/ouster/scripting.html (his original paper) because all his statements about systems programming languages reinforces my claim that Python is not a systems programming language.
To give you an example of what is systems programming, I have helped developed operating systems kernels, virtual machine monitors, and distributed networked systems. All of these things would be considered systems programming.
See http://en.wikipedia.org/wiki/System_programming for more information.