That's fair, I'll add the reference as you wrote it into the post. @DavidRoberts

Oops. I swapped it out for ArXiv link. Any parameterization that works will do. @MartinSeysen

To my understanding the scipy function just yields a random special unitary, not a parameterized one. There are a few quantum computing packages which also yield random special unitaries, but none that I have found parameterize the unitaries. @MartinSeysen