Generic Tray Creator Script (with rounded bin floors)

This is not about a specific model, it's about my python/SolidPython script that creates arbitrary grid trays (with rounded bottoms so there's no corners), useful for organizing lots of small items. Especially nice for creating board game organizers.
The script is attached, it is called "generic_tray.py". You run it from the command line with the grid dimensions and it will spit out a .scad file and [optionally] a .stl file. It will also show you the [approximate] volume of each bin.
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USAGE
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***ALL UNITS ARE MILLIMETERS***
The tray will be specified by the dimensions of each row/column,
provided as two arrays. The example screenshot shows the terminal after running the tool. Use the following command-line call to create the example in the screenshot (x-axis always first).
`python generic_tray.py [40,60,35,20] [30,40]`
Make sure there are no spaces before or after the commas in the lists: You can add extra args to adjust floor- and wall-thicknes