Propagate a key press or release event to the focus widget and
up the focus container chain until a widget handles @event.
This is normally called by the default ::key_press_event and
::key_release_event handlers for toplevel windows,
however in some cases it may be useful to call this directly when
overriding the standard key handling for a toplevel window.
Propagate a key press or release event to the focus widget and up the focus container chain until a widget handles @event. This is normally called by the default ::key_press_event and ::key_release_event handlers for toplevel windows, however in some cases it may be useful to call this directly when overriding the standard key handling for a toplevel window.