Using Skyfield to determine observing window

I’m trying to write a function that will give me the observing window for a given star on a given date from a given location, with also an optional minimum altitude.

Observing Location (long/lat/alt)
Target Star (ra/de)
Min Altitude

Rise Time
Set Time

where rise and set times are the times at which the star rises above and sets below the horizon (or min altitude if specified).

I’m not looking for someone to provide the solution but I could do with a steer towards the most appropriate Skyfield apis.