This is a simple python dev environment using docker.
If you open this in visual studio code, it should give you a prompt to open the folder in a container. If not, you can open the command palette and search for Remote-Containers: Open Folder in Container... and select the folder.
You can add packages to the requirements.txt file and then either run pip install -r requirements.txt in the terminal inside the container, or restart the container. This will install the packages in the container.
Note: requirements and requirements-dev are separated so that you can install packages that are only needed for development in the dev container. This is useful for things like linters and formatters.