Domino standard environments generally have a version of python that is a few versions back from the most recent. This article is intended to just provide docker instructions to upgrade to python 3.8. It should work in most standard Domino environments, but your speed may vary if there are other customizations already added or the environment you are using is particularly old.
The docker code to add is...
#Install python 3.8
RUN apt update && apt install build-essential zlib1g-dev libncurses5-dev libgdbm-dev libnss3-dev libssl-dev libreadline-dev libffi-dev wget libsqlite3-dev -y
RUN cd /tmp && wget https://www.python.org/ftp/python/3.8.1/Python-3.8.1.tgz && tar -xvzf Python-3.8.1.tgz && cd Python-3.8.1 && ./configure && make altinstall && cp /tmp/Python-3.8.1/python /opt/conda/bin
RUN cd /tmp && curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py && \
python /tmp/get-pip.py --force-reinstall
RUN pip install --upgrade ipython notebook
RUN rm -rf /tmp/*