#编译: make

#编译安装: make install

[root@web Python-3.9.0]# /usr/local/python3/bin/python3.9
Python 3.9.0 (default, Oct 29 2020, 15:04:23)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-39)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>
然后再按照上面的方式 进行切换到python3
先备份 python2
mv /usr/bin/python /usr/bin/python.bak
ln -s /usr/local/python3/bin/python3 /usr/bin/python3
ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3
并将/usr/local/python3/bin加入PATH
PATH=$PATH:$HOME/bin:/usr/local/python3/bin
export PATH
保存之后 执行
source /etc/profile