python-systemd | Python wrappers for systemd functionality

The error occurred because you have installed your dependencies using Sudo. This has installed your pip dependencies only for Sudo users, whilst you are running your Django application as a non-sudo user. This is the reason why you didn't saw your packages when you did pip freeze but you saw them after doing sudo pip3 freeze

To solve this

1. Install python3-venv with this command sudo apt-get install python3-venv
2. Create a virtual environment python3 -m venv env this command will create a virtual environment named env
3. Activate the virtual environment with this command source env/bin/activate

Once you have done this you will see a (env) before your shell which indicates that your virtual environment is activated now need to install the dependencies inside this

1. cd to your requirements.txt and type pip3 install -r requirements.txt make sure you do it without sudo (because you will run your Django app in your web server as a non-sudo privilege user for security reasons)

After this, you can run your Django app with your virtual environment kept active.