Hotkey for Master Guides in Keynote

Is there a way to set a Keyboard shortcut to Show / Hide Master Guides in Keynote? Getting at the command from the subsection of a subsection of the menu is a bit of a pain when you have to do this a lot.

Or at least is there a way to include the command in the toolbar when customizing it ? I can do this for normal guides, but not for Master Guides....

Please Apple, make this designer's job easier and I will stop complaining about having to use Keynote for presentations at work 😉