lsb_release -a查看系统版本。sudo apt update和sudo apt upgrade更新系统。sudo apt install build-essential libssl-dev zlib1g-dev libbz2-dev libreadline-dev libsqlite3-dev。sudo add-apt-repository ppa:deadsnakes/ppasudo apt updatesudo apt install python3.x(x为目标版本号)。sudo sed -i 's/archive.ubuntu.com/mirrors.aliyun.com/g' /etc/apt/sources.listpip install -i https://pypi.tuna.tsinghua.edu.cn/simple <package>。wget https://www.python.org/ftp/python/3.x.x/Python-3.x.x.tgztar -zxvf Python-3.x.x.tgzcd Python-3.x.xsudo ./configuresudo makesudo make install。sudo执行安装命令获取权限。PATH:echo 'export PATH=/usr/local/bin:$PATH' >> ~/.bashrc,然后source ~/.bashrc。sudo apt install python3-venvpython3 -m venv myenvsource myenv/bin/activate。/var/log/apt/history.log或安装时的详细输出(sudo apt install python3 --verbose)定位具体错误。若以上方法无效,建议提供具体错误信息以便进一步排查。