UPDATE 2022:
--->
I enforced the 2 mounting wings because they broke twice already.
I extended the inner tube diameter slightly because my lock was sitting too tightly.
The distance between the mounting holes is 62mm which works fine for my bicycle. Apparently the standard is 65mm. Sorry. Please help yourself making one of the holes a long hole in your slicer ;-)
--->
Inspired by Origamika's design I made some adjustments to fit my own Abus U-Mini 415 which has a thinner body.
Here are the diameters of my lock:

• U-shackle: 12mm
• U-shackle with rubber: 17mm
• Body: 37mm

my tube has both a 12mm hole on one side and a 17mm hole on the other.
So you can either insert the bare shackle or the rubber-protected shackle.
maybe the holes are a bit tight, but it works for me. I don't want the lock to shake
while riding on cobblestone roads.

Mine printed very well in one piece - no problem with overhangs on top of the holes.
However I included seperated STLs just in case your printer doesn't work so well.
You can easily glue them together with regular instant glue. I made sure to extrude some notch for it to be perfectly aligned.

Geeetech A10

No

No

200

80

infill should be at least 80% for stability.