Kinda does f.lux for Philips Hue lights. Takes one input parameter, brightness percentage, which defaults to 100 if omitted. Assumes you've already set your bridge up for the Hue API. Fill in your own username, and lat/long. group '0' means 'all'.
Requires pysolar.
BTW, I made absolutely zero attempt to make this code good, maintainable, extensible, etc. It's just a script I run on my laptop at home that I was asked to upload. I promise my professional software is better :)