The key_press_event signal is emitted when a key is pressed.
The signal emission will reoccur at the key-repeat rate when the key is kept pressed.
To receive this signal, the Window associated to the widget needs to enable the KEY_PRESS_MASK mask.
This signal will be sent to the grab widget if there is one.
the EventKey which triggered this signal.
true to stop other handlers from being invoked for the event. false to propagate the event further.