Updates: v0.1.0: Initial beta version based on the mathematical model from the SciFest project called "How Population Density Influences Light Pollution". v0.1.1: Allowed population density figures to be inputted. v0.5.0: The mathematical model is updated, and is now based on the BT Young Scientist project called "Is it Possible to Create a Mathematical Model to Predict Photopollution Based on Population Density in Munster". v0.5.1: Includes licensing agreement. v0.5.2: Updated population density figures to include the figures from the 2016 Census. v0.5.3: See those bugs, no? Well, they are gone! v0.5.4: Slight changes to the mathematical model. v0.6.0: Slight changes to the grading system and mathematical model. v0.6.1: Fixed TypeError when entering a text value for population density. v0.6.2: See those bugs, no? Well, they are gone! v0.6.3: Updated to support Windows and macOS alongside Linux. v1.0.0: Worldwide Public Release on Github! v1.0.1: Day 1 Bug Patch. v1.1.0: Let's Get Py Crazy! update. v1.1.1: Small Changes and Fixes v1.2.0: Major Changes to Data Calculations v1.5.0: Fin 2018 update v1.5.1: Emergency Bug Fix Update v1.5.2: Small Changes and Fixes v1.6.0: Errer Update v2.0.0: BTYSTE Update v3.0.0: Sky Quality Update v4.0.0: British Isles Update