def remove(self, client: Window) -> Window | None:
        """Called whenever a window is removed from the group

        Called whether the layout is current or not. The layout should just
        de-register the window from its data structures, without unmapping the
        window.

        Returns the "next" window that should gain focus or None.
        """
Called whenever a window is removed from the group

        Called whether the layout is current or not. The layout should just
        de-register the window from its data structures, without unmapping the
        window.

        Returns the "next" window that should gain focus or None.
        
libqtile/layout/base.py