[xmonad] Flip workspaces using a multihead display

Hi, I use two monitors on my machine. I often find that I'd like to switch the workspace on the right with the one on the left, and the left with the right. This currently takes two key strokes which change depending on which side I happen to be focused on, and which workspaces I'm currently viewing. Which is annoying. Can I add a single key stroke to achieve this? Thanks, -- "I know you think you understand what you thought I said but I'm not sure you realize that what you heard is not what I meant" -- Alan Greenspan