Determines if the edited accelerators are GTK+ accelerators. If they are, consumed modifiers are suppressed, only accelerators accepted by GTK+ are allowed, and the accelerators are rendered in the same way as they are in menus.
If the mode is set to gtk.types.CellRendererAccelMode.ModifierTap then bare modifiers can be set as accelerators by tapping (ie: pressing and immediately releasing) them.
Builder instance for fluent chaining
Set accelMode property.