Code review comment for lp:~kartiksinghal/polly/patch-for-undo-redo-for-compose-box

Sorry it took this long. Only very small things now:

1) I don't think considering both z and Z is necessary.

2) Please use multiple "=="s instead of using "in". Yes, I'm aware this is less pythonic, but it's still better than inconsistency in a single point.

3) There is an extra linebreak at the end, after the redo method.

I promise the next version will not take more than one day!