Expobar E61 inclined portafilter holder / tamp stand

I got sick of trying to balance my single spout portafilter on the edge of the bench when tamping, and I also often need somewhere to put it down when my toddler comes bailing up needing something urgently!

This suits the Expobar inclined handle, which is at 10 degrees to the basket plane.
It's designed to hold it by the ramps so it may be usable for other E61 portafilters (possibly with tweaks to the handle support). STEP file is included for relatively easy tweaking.

I've happily printe