def normpath(filename: _Path) -> str:
    """Normalize a file/dir name for comparison purposes."""
    # See pkg_resources.normalize_path for notes about cygwin
    file = os.path.abspath(filename) if sys.platform == 'cygwin' else filename
    return os.path.normcase(os.path.realpath(os.path.normpath(file)))
Normalize a file/dir name for comparison purposes.
product/gradle-plugin/src/main/python/setuptools/_path.py