Centos安装python3

安装需要的依赖

yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gcc make zlib zlib-devel -y

拉取python安装包

wget https://www.python.org/ftp/python/3.6.8/Python-3.6.8.tar.xz

解压python源码包

xz -d Python-3.6.8.tar.xz
tar -xf Python-3.6.8.tar

编译安装

cd Python-3.6.8
./configure prefix=/usr/local/python3
make -j 4 && make install

编译安装完成后会在/usr/local下生成python3目录

添加软链接，并备份之前的链接目录

mv /usr/bin/python /usr/bin/python.bak
ln -s /usr/local/python3/bin/python3.6 /usr/bin/python

更改配置文件，配置yum，因为yum使用的是python2

vim /usr/bin/yum
改：#! /usr/bin/python
为：#! /usr/bin/python2

更改配置文件

vim /usr/libexec/urlgrabber-ext-down
改：#! /usr/bin/python
为：#! /usr/bin/python2

验证版本号

[root@localhost ~]# python -V
Python 3.6.8

使用python2版本

[root@localhost ~]# python2
Python 2.7.5 (default, Oct 30 2018, 23:45:53) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-36)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> 

使用python3版本

python
Python 3.6.8 (default, Nov 17 2021, 16:00:46) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-39)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 

配置pip软链接

rm  -rf /usr/bin/pip
ln -s /usr/local/python3/bin/pip3  /usr/bin/pip

查看pip版本，并升级pip

[root@localhost ~]pip -V
pip 18.1 from /usr/local/python3/lib/python3.6/site-packages/pip (python 3.6)
[root@localhost ~]pip install --upgrade pip
[root@localhost ~]# pip -V
pip 21.3.1 from /usr/local/python3/lib/python3.6/site-packages/pip (python 3.6)