It would be good to have a cell-like stylesheet=stylesheet so that others can re-import it. You could also call the stylesheet here if you want to use it and style the cells below!

There's a bit of duplication here with the core library: sum_list doesn't exist in core (annoyingly, I want to add that at some point) sqrt exists as Math.sqrt (undocumented, I've just realised) normal_from_mean_and_sd(x, y) exists as lognormal({mean: x, stdev: y}) mean and stdev of lognormal dist can be gotten through mean(lognormal()) and stdev(lognormal()) [I think the latter is somewhat new]