Importing System Site Packages

You can use your system’s Python packages such as those built by your linux distrobution and installed like sudo apt install python3-pymssql inside of a virtual environment by adding the --system-site-packages flag when creating the virtual environment.

sudo apt install python3-pymssql
python3 -m venv --system-site-packages .venv
source .venv/bin/activate
python -c "import pymssql"

This saved me after spending far more time than I like trying to install pymssql on an old RaspberryPi which even the team at PiWheels.org don’t provide a wheel for.