ModuleNotFoundError: No module named '_aqt'

Anki Desktop
1

I get this error when using the Slackware SlackBuild for Anki 2.1.60:

   Traceback (most recent call last):
     File "/usr/bin/anki", line 5, in <module>
       from aqt import run
     File "/usr/lib64/python3.9/site-packages/aqt/__init__.py", line
   46, in <module>
       from aqt import gui_hooks
     File "/usr/lib64/python3.9/site-packages/aqt/gui_hooks.py", line
   11, in <module>
       from _aqt.hooks import *
   ModuleNotFoundError: No module named '_aqt'
2

https://docs.ankiweb.net/platform/linux/distro-packages.html

3

I never had this problem on with earlier versions of Anki and AQT packages downloaded from PyPi.

Why does the error say “aqt" (with the "”) and not “aqt”?