Ubuntu 18.04

  apt-add-repository -y ppa:deadsnakes
  apt update
  apt install python3.8

  export VERSION=3.10.14
  sudo apt install -y build-essential zlib1g-dev libncurses5-dev libgdbm-dev libnss3-dev libssl-dev libreadline-dev libffi-dev wget
  wget https://www.python.org/ftp/python/${VERSION}/Python-${VERSION}.tgz
  tar -xf Python-${VERSION}.tgz
  cd Python-${VERSION}
  make -j $(nproc)
  sudo make altinstall