Black rubber tube hanging from rear of car VOLVO XC40 (536) (10.2017 - ...)

Hi, would anyone know what the black tube hanging from the rear driver side of my car is (Volvo XC40 Petrol 2018).

Opposite side to exhaust but same side as fuel cap. I can’t see where the loose end would have connected to. The third picture which shows the other end is still clipped in place although noticed the join is very worn and torn here.

A quick google and some message board suggested drain pipe from fuel filler. The back washer still works as someone else suggested that could be it. There’s no visible leaks and no reduction in engine performance. So any pointers would be great as either way I’ll need to replace the tube just identifying what I need and how easy it is for a diy job.

Thanks!