Your report seems really odd and not related to pysim but rather some
unfortunate mixup of python library installation. Hard to tell from the
distance.
Have you tried maybe running 'python3' (or 'ipython3') and entering
import construct
on the prompt?
Is there maybe some discrepancy between /usr/local/lib, /usr/lib and your
~/.local/lib python library locations?
Maybe try running from a different user account, just in case your user's
python config is somehow confused?
~N