Scripted hotbar changing widget

[Qarma]

Dunno whats possible or not but I would like a small widget that looks just like the current hotbar bank switch but which changed the bank of all three hot bars by 3. ie I click one button and the first hotbar changes from bank 1 to bank 4, the second hotbar changes from 2 to 5 and the third hotbar changes from 3 to 6.