While implementing the Windows installer for PEP 453 in issue 19550, MvL pointed out that, *by default*, the installers should be able to uninstall everything they install.

At the moment, if they install pip by default, that's not accurate, as we don't currently have the appropriate command defined to do the uninstall.

For beta 1, Martin just went with the option of leaving the option off by default, but it would be good to resolve the uninstallation problem and allow it to be enabled by default.

My suggestion for a design requirement is:

    If a user installs CPython use the binary installer, makes no changes to the installation options, makes no use of the installed pip and then uninstalls CPython, then there should be no CPython related files left on their system.

If they *do* use the installed pip (whether to upgrade pip itself or to install other packages), then files may potentially be left behind, since they're seen as user data files by CPython.

I also think it's OK if uninstalling CPython removes setuptools and pip from that installation's site-packages, even if they had been upgraded following the original installation.