def METHOD_NAME(self):
    """
    Return the .focus_position values starting from this container
    and proceeding along each child widget until reaching a leaf
    (non-container) widget.
    """
    out = []
    w = self
    while True:
        try:
            p = w.focus_position
        except IndexError:
            return out
        out.append(p)
        w = w.focus.base_widget