Iterate over all child paths of `parent_path` matched by this
        selector.  This can contain parent_path itself.

def select_from(self, parent_path):
        """Iterate over all child paths of `parent_path` matched by this
        selector.  This can contain parent_path itself."""
        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)