Currently, pathlib contains the following check for the OS in the import section:

    try:
        import nt
    except ImportError:
        nt = None
    else:
        if sys.getwindowsversion()[:2] >= (6, 0):
            from nt import _getfinalpathname
        else:
            supports_symlinks = False
            _getfinalpathname = None

I would like to suggest to switch this on testing for the value of `os.name` (as `PurePath.__new__` does), or possibly testing whether `sys.getwindowsversion` exists: the `nt` module is not publicly defined, so it wouldn't be unreasonable to have a file named `nt.py` on an Unix system (where this shouldn't cause any problems), in which case importing `pathlib` raises an AttributeError at the `getwindowsversion` line.