def is_transient_for(self) -> base.WindowType | None:
        """What window is this window a transient window for?"""
        parent = self.surface.parent
        if parent:
            for win in self.qtile.windows_map.values():
                if isinstance(win, XWindow) and win.surface == parent:
                    return win
        return None
What window is this window a transient window for?
libqtile/backend/wayland/xwindow.py