How to use the pathlib2.__init__._Selector function in pathlib2

def try_iter():
            path = parent_path._make_child_relpath(self.name)
            if (is_dir if self.dironly else exists)(path):
                for p in self.successor._select_from(
                        path, is_dir, exists, scandir):
                    yield p

        def except_iter(exc):
            return
            yield

        for x in _try_except_permissionerror_iter(try_iter, except_iter):
            yield x


class _WildcardSelector(_Selector):

    def __init__(self, pat, child_parts):
        self.pat = re.compile(fnmatch.translate(pat))
        _Selector.__init__(self, child_parts)

    def _select_from(self, parent_path, is_dir, exists, scandir):
        def try_iter():
            cf = parent_path._flavour.casefold
            entries = list(scandir(parent_path))
            for entry in entries:
                if not self.dironly or entry.is_dir():
                    name = entry.name
                    casefolded = cf(name)
                    if self.pat.match(casefolded):
                        path = parent_path._make_child_relpath(name)
                        for p in self.successor._select_from(

casefolded = cf(name)
                    if self.pat.match(casefolded):
                        path = parent_path._make_child_relpath(name)
                        for p in self.successor._select_from(
                                path, is_dir, exists, scandir):
                            yield p

        def except_iter(exc):
            return
            yield

        for x in _try_except_permissionerror_iter(try_iter, except_iter):
            yield x


class _RecursiveWildcardSelector(_Selector):

    def __init__(self, pat, child_parts):
        _Selector.__init__(self, child_parts)

    def _iterate_directories(self, parent_path, is_dir, scandir):
        yield parent_path

        def try_iter():
            entries = list(scandir(parent_path))
            for entry in entries:
                entry_is_dir = False
                try:
                    entry_is_dir = entry.is_dir()
                except OSError as e:
                    if not _ignore_error(e):
                        raise

path_cls = type(parent_path)
        is_dir = path_cls.is_dir
        exists = path_cls.exists
        scandir = parent_path._accessor.scandir
        if not is_dir(parent_path):
            return iter([])
        return self._select_from(parent_path, is_dir, exists, scandir)


class _TerminatingSelector:

    def _select_from(self, parent_path, is_dir, exists, scandir):
        yield parent_path


class _PreciseSelector(_Selector):

    def __init__(self, name, child_parts):
        self.name = name
        _Selector.__init__(self, child_parts)

    def _select_from(self, parent_path, is_dir, exists, scandir):
        def try_iter():
            path = parent_path._make_child_relpath(self.name)
            if (is_dir if self.dironly else exists)(path):
                for p in self.successor._select_from(
                        path, is_dir, exists, scandir):
                    yield p

        def except_iter(exc):
            return
            yield