When the hangup key is pressed, the interpreter exits immediately, thereby possibly crashing while doing internal cleanup on native resources that should have been closed.
This patch simply ignores the EndKeyCloseEvent, which results in python being switched to the background (at least on my device). Note that after installation you might have to reboot your device before the change is effective due to dlls being cached in memory.
Perhaps an attribute could be added to appuifw.app to make the behaviour user configurable.
patch relative to release 1.4.1