Write a program to generate sudoku puzzles with a unique solution.

In Postscript.

In such a way that if I print 5 copies of your program, I get five distinct sudoku puzzles.

Clarifications

• The puzzles should, at most, specify 25 of the 81 spaces.

• Programs that simply take an existing puzzle and apply transformations will be frowned upon mightly.

• If it crashes my printer, it doesn’t qualify.