Given MvL's comment above, my suggestion is that we add an "ensurepip._uninstall" submodule that uninstalls pip and setuptools if it is invoked as __main__ and the following snippet results in uinstall being set to True:

    try:
        import pip
    except ImportError:
        uninstall = False
    else:
        uninstall = (pip.__version__ == ensurepip.version())

(I believe PIP_VERSION in ensurepip is currently wrong, as it has an extra dot that shouldn't be there, but we can fix that as part of implementing this, and tweak the test in test_venv to ensure it doesn't get out of sync again)