python3_0">一、安装python3

【注意】全程在 root 权限下执行

1、先安装openssl，不然以后python会遇到出错：ModuleNotFoundError: No module named '_ssl'

curl http://www.openssl.org/source/openssl-1.1.1.tar.gz -o openssl-1.1.1.tar.gz
tar -zxvf openssl-1.1.1.tar.gz
cd openssl-1.1.1
./config --prefix=/usr/local/openssl shared zlib
make && make install

2、设置系统环境变量LD_LIBRARY_PATH

echo "export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/openssl/lib" >>  /etc/profile
source /etc/profile

3、安装各种依赖，以防python导入发生一些错误，如：ModuleNotFoundError: No module named ‘_ctypes‘

yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel gcc libffi-devel

yum不可用点这:【最新可用】centOS7替换阿里yum源

4、安装python3

curl https://www.python.org/ftp/python/3.10.11/Python-3.10.11.tar.xz -o Python-3.10.11.tar.xz  # 下载安装包
tar -zxvf Python-3.10.11.tar.xz     #(解压安装包)
./configure --prefix=/usr/local//python3 --with-openssl=/usr/local//openssl     # (配置安装目录，指定openssl环境的安装目录)
make && make install      #（编译、安装）

安装成功后执行：python3 -V

二、修改环境变量

修改环境变量python为python3，使其执行python -V 输出为python3的版本

ln -s /usr/local/python3/bin/pip3  /usr/bin/pip        # (pip命令行调用指向pip3)
ln -s /usr/local/python3/bin/python3  /usr/bin/python         # (python命令行调用指向python3)

修改yum的python配置，不然修改环境变量后yum用不了

sed -i '1s|.*|#!/usr/bin/python2.7|' /usr/bin/yum
sed -i '1s|.*|#!/usr/bin/python2.7|' /usr/libexec/urlgrabber-ext-down