Originally I have designed this to hang the broom at the wall but this mount can also be useful to attach any tools with cylindrical handles. I know it sounds a lot easier just to drill a hole to the broom handle and hit a nail into the wall but:
I am not allowed to use nails in our apartment
to solve this problem with a nail does not satisfy my print-in-place hinge addiction at all ;)
I have seen a lot of similar solutions but all of those used metal rivets or nuts & bolts. This is a print-in-place design with built in hinges so no need for assembly.
The uploaded STLs are sized to fit to my LEIFHEIT broom's telescopic handle (~≥24 mm diameter) but as I attached the Fusion 360 file you can alter it by changing the d_broome parameter. My advice is to reduce the mount's internal diameter by ~0.2-0.4 mm in order to create some tension - the built in spring has enough reserve to hold it tight.
I have also created a model with a T shaped bottom mount which lets you to attach the mount without any screws just by using 3M's amazing velcro-based Command tape.