Errors trying to run apt-get update

Description: Linux Lite 4.2
Release: 18.04
Codename: bionic
Kernel 4.15.0-65-generic #74-Ubuntu SMP Tue Sep 17 17:06:04 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

Hit:1 http://packages.microsoft.com/repos/vscode stable InRelease
Hit:2 http://us.archive.ubuntu.com/ubuntu bionic InRelease
Hit:3 http://us.archive.ubuntu.com/ubuntu bionic-security InRelease
Hit:4 http://us.archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit:5 http://archive.canonical.com/ubuntu bionic InRelease
Hit:6 http://us.archive.ubuntu.com/ubuntu bionic-backports InRelease
Hit:7 http://ppa.launchpad.net/otto-kesselgulasch/gimp/ubuntu bionic InRelease
Hit:8 http://ppa.launchpad.net/teejee2008/ppa/ubuntu bionic InRelease
Hit:9 http://repo.linuxliteos.com/linuxlite diamond InRelease
Traceback (most recent call last):
File "/usr/lib/cnf-update-db", line 8, in <module>
from CommandNotFound.db.creator import DbCreator
File "/usr/lib/python3/dist-packages/CommandNotFound/db/creator.py", line 11, in <module>
import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'
Error in sys.excepthook:
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63, in apport_excepthook
from apport.fileutils import likely_packaged, get_recent_crashes
File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in <module>
from apport.report import Report
File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in <module>
import apport.fileutils
File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23, in <module>
from apport.packaging_impl import impl as packaging
File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line 24, in <module>
import apt
File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in <module>
import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'

Original exception was:
Traceback (most recent call last):
File "/usr/lib/cnf-update-db", line 8, in <module>
from CommandNotFound.db.creator import DbCreator
File "/usr/lib/python3/dist-packages/CommandNotFound/db/creator.py", line 11, in <module>
import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'
Reading package lists... Done
E: Problem executing scripts APT::Update::Post-Invoke-Success 'if /usr/bin/test -w /var/lib/command-not-found/ -a -e /usr/lib/cnf-update-db; then /usr/lib/cnf-update-db > /dev/null; fi'
E: Sub-process returned an error code

that is quite interesting. The apt_pkg module can be found in the package python3-apt, so you need to [re]install it somehow.
If there was no other way you need to download the package and install it with dpkg.
probably from here: http://us.archive.ubuntu.com/ubuntu/.../p/python-apt/

I believe you assessment about python3-apt being a little buggered.

Tried to update, install & reinstall python3-apt
Tried to update apt-get

sudo apt-get install python-apt
sudo apt-get update
sudo apt-get install python3-apt --reinstall
sudo apt-get update
sudo apt autoremove

Ultimately came across a similar thread, with similar issue
advice given:

cd /usr/lib/python3/dist-packages
ls -la /usr/lib/python3/dist-packages
sudo cp apt_pkg.cpython-36m-x86_64-linux-gnu.so apt_pkg.so

These all work now.
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install

Thanks for the assistance.

glad to head that. If you think your problem is solved please mark the thread solved.