检查系统是否已经装了python
python2 --version
python3 --version下载python安装包
wget https://www.python.org/ftp/python/3.9.0/Python-3.9.0.tgz如果未安装wget，使用命令进行安装
yum -y install wget解压安装包
tar -zxvf Python-3.9.0.tgz准备编译环境
yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gcc make创建安装目录
mkdir -p /usr/local/python3进入到解压后的安装包内
cd Python-3.9.0执行下述命令指定安装目录
./configure --prefix=/usr/local/python3进行安装
make && make install
创建软连接，依次执行以下代码
mv /usr/bin/python /usr/bin/python.bak
ln -s /usr/local/python3/bin/python3.9 /usr/bin/python
ln -s /usr/local/python3/bin/pip3.9 /usr/bin/pip3配置系统环境变量
vi ~/.bash_profile最后一行追加
export PYTHON_HOME=/usr/local/python3
export PATH=$PYTHON_HOME/bin:$PATH执行命令使环境变量生效
source ~/.bash_profile
