Esempio per app Flask
Dockerfile
FROM ubuntu:18.04
ENV TZ=Europe/Rome
RUN apt-get -y update
RUN apt-get -y upgrade
RUN apt install -y python3.7
RUN pip3 install flask
COPY . /usr/src/app/
WORKDIR /usr/src/app/
EXPOSE 5000
ENTRYPOINT ["/startup.sh"]
CMD ["python3","/usr/src/app/app.py"]

docker build -t image:version .

docker push image:version

docker pull image:version

docker run --rm -it -p 5000:5000 --network="host" image:version