Linux系统安装更新Python3.x版本详细步骤

Linux系统中默认自带的Python版本都比较低，通常是Python2.7，对于一些要求Python高版本的项目来说就会无法继续运行，所以需要升级到python3环境，本文提供下升级Python版本的详细代码，方便后面用于查询。

Debian/Ubuntu系统

安装Python3.8

cat <<"EOF" | bash
apt install build-essential zlib1g-dev libncurses5-dev libgdbm-dev libnss3-dev libssl-dev libsqlite3-dev libreadline-dev libffi-dev curl libbz2-dev -y && \
curl -O https://www.python.org/ftp/python/3.8.2/Python-3.8.2.tar.xz && \
tar -xf Python-3.8.2.tar.xz && \
cd Python-3.8.2 && \
./configure --enable-optimizations && \
make -j 4 && \
sudo make altinstall && \
python3.8 --version
EOF
 
apt update && apt install python3-pip

安装Python3.10

apt update && apt upgrade -y
 
apt install git wget curl screen htop vim sudo -y
 
apt-get --purge remove python3 python3-pip -y
 
apt install build-essential libreadline-dev libncursesw5-dev libssl-dev libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev libffi-dev zlib1g-dev -y
 
wget https://www.python.org/ftp/python/3.10.8/Python-3.10.8.tgz
 
tar -xzvf Python-3.10.8.tgz
 
cd Python-3.10.8
 
./configure --prefix=/usr/local/python3
 
make altinstall
 
rm -f /usr/bin/python3
rm -f /usr/local/bin/pip3
ln -s /usr/local/python3/bin/python3.10 /usr/bin/python3
ln -s /usr/local/python3/bin/pip3.10 /usr/bin/pip3
 
python3 -m pip install --upgrade pip
 
python3 -V && pip3 -V

Centos7系统

安装Python3.8

yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gcc make libffi-devel wget
 
wget https://www.python.org/ftp/python/3.8.2/Python-3.8.2.tar.xz
tar -xf Python-3.8.2.tar.xz
cd Python-3.8.2
./configure prefix=/usr/local/python3
make && make install
ln -s /usr/local/python3/bin/python3.8 /usr/bin/python3
ln -s /usr/local/python3/bin/pip3.8 /usr/bin/pip3
 
python3.8 --version

这里没有直接链接到python，所以输入python的话还是会进入python2.7，输入python3才会进入python3.8，因为yum需要用到python2才能执行，执意要链接的话需要手动修改yum配置：

vi /usr/bin/yum
把 #! /usr/bin/python 修改为 #! /usr/bin/python2
 
vi /usr/libexec/urlgrabber-ext-down
把 #! /usr/bin/python 修改为 #! /usr/bin/python2

配置默认版本

如果机器内有多个python版本，可以通过设置优先级来默认使用哪个版本

sudo update-alternatives --install /usr/bin/python python /usr/bin/python2 1
sudo update-alternatives --install /usr/bin/python python /usr/bin/python3 2