Funnel / mixing hopper for filling 2.75" bird feeder

I couldn't find a funnel that quite fit this need, so I quickly put one together in OpenSCAD - parameterized file included.  Provides a close, stable fit thanks to the bar notch so the feeder doesn't fall over when I dump seed into it.

Added: a model for a “Hopper Stopper”, to allow (very roughly) mixing 2 types of seed/food. Put it in the funnel, put one seed type each side, gently lift it out. Results, ironically, are… mixed. But it's optional; the funnel works fine alone.

Print is in PolyTerra Cotton white @ 0.3mm with a randomized seam in the 3mf/gcode, hence the rough surface texture. (gcode for the plug is 0.2mm, just to see the difference). No supports are needed if printed in the orientation in the 3mf files provided, ie flip the plug STL to print it if you just use that.