Sudoku solvers and cairo graphics

I have decided to play a bit with constraint programming, so I'm rewriting my logic game solvers as constraint programs. For that I'm using the minion constraint solver to which I interface through python; I wrote a simple parser of minion's textual output. I wanted some pretty-printing, and doing it in purely textual mode has shown to be rather tedious to code. So I turned to the excellent cairo graphics library for drawing solutions. The library is surprisingly simple to use, and also comes with python bindings. Now I'm working on another puzzle, and after cleaning up the code a bit, I'll upload the new package.