Docker Ubuntu 에 python 3.x 설치하기 - DanielWorld/SoftwareTech GitHub Wiki

https://www.itsupportwale.com/blog/how-to-upgrade-to-python-3-8-on-ubuntu-18-04-lts/

실행

$ apt update && apt upgrade && apt-get update
$ apt list | grep python3.x  # 설치가능한 python3.x 버전 확인
$ apt install python3.x
$ update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.x 1

$ python3 -V
$ apt install python3-pip
$ python3 -m pip list

uninstall

$ apt remove python3.x

참고 : https://www.linuxcapable.com/install-python-3-8-on-ubuntu-linux/