Answers for "install python3 and python pip in docker"

install python3 in dockerfile

RUN apk upgrade --update && apk add --no-cache python3 python3-dev

install python3 and python pip in docker

Create Dockerfile : 

FROM python:3-alpine

RUN python -m pip install --upgrade pip

RUN pip3 install requests paho-mqtt

COPY NumSide.py /home/mehdi/Download/NumSide.py

CMD ["python","/home/mehdi/Download/NumSide.py"]