This mod adds a python3 to the docker container, to be installed/updated during container start.
In docker arguments, set an environment variable DOCKER_MODS=linuxserver/mods:code-server-python3
If adding multiple mods, enter them in an array separated by |, such as DOCKER_MODS=linuxserver/mods:code-server-python3|linuxserver/mods:code-server-mod2
Based on https://github.com/linuxserver/docker-mods/tree/code-server-python3