Jython: Cannot import Transformation in openHAB 3.4

[rkrisi (Kristof Rado)]

Since I upgraded to openHAB 3.4, my Jython scripts cannot import the Transformation module.

ImportError: cannot import name Transformation in /etc/openhab/automation/jsr223/python/personal/speedtest.py at line number 6

Why?

[Mherwege (Mark Herwege)]

See here for how to solve this.