Snapmaker Artisan dual filament sensor

It is a remix of https://www.thingiverse.com/thing:2147179

Why to do such a thing when your Snapmaker Artisan already has built-in filament sensors? Because when use use OctoPrint then OctoPrint can't use original Snapmaker's sensors (god dammit) and you need to add external ones connecting them directly to OctoPi.

My solutions allow you to monitor both filaments and get immediate email when filament is running out. You have enough time (about one meter of filament left) to go to machine and insert new filament just after the old one, without pausing, stopping or making any other distraction to printing process.

HARDWARE

1) Print all once except cover (x2) and body (x2).

2) Insert electronic into bodies and close covers.

3) Glue ball to one of the bodies (see photos).

4) Mount all to Artisan's enclosure using screw M3x20 (I had one original from Snapmaker, search your stuff).

5) Connect first sensor (e.g. the one with main material) to board pins. On Raspberry P