what does x reprsent in this code ?

[bowlofred]

That depends on the specifics of your system, not on python itself.

But in general, you don't want to uninstall packages that you didn't install yourself. There might be hidden dependencies that just assume that some ancient version of python is there and runnable.

Better to just put the version on that you want, and make sure it's in your PATH so you run it. You can ignore the other packages on the system. Other than a bit of disk space, I see no benefit to removing the system-installed packages.