Bug#978657: unknown-horizons: Crash on startup with xml AttributeError "no attribute 'getchildren'"

[Simon McVittie]

Control: reassign -1 python3-fife 0.4.2-2
Control: affects -1 + unknown-horizons

On Tue, 29 Dec 2020 at 20:54:44 +0100, Steffen Langenbach wrote:
> I encountered a problem starting unknown-horizons.
...
>   File "/usr/lib/python3/dist-
> packages/fife/extensions/serializers/simplexml.py", line 386, in _validateTree
>     for c in self._root_element.getchildren():
> AttributeError: 'xml.etree.ElementTree.Element' object has no attribute
> 'getchildren'

This looks like an incompatibility between fife and Python 3.9, similar to
<https://bugs.debian.org/975818>. The getchildren method was removed
from xml.etree in the Python 3.9 standard library, and fife probably
needs to use "for c in self._root_element:" instead.

    smcv