官网： https://github.com/pyenv/pyenv
功能：
管理Python解释器
管理Python版本
管理python的虚拟环境
安装步骤
1）创建www用户，使用www用户登录系统
[root@python ~]# useradd www && echo "Aa123456" | passwd --stdin www
[root@python ~]# su - www
2）安装依赖包
[www@python ~]$ sudo yum -y install git gcc make patch gdbm-devel openssl-devel sqlite-devel readline-devel zlib-devel bzip-devel
3）安装pyenv
[www@python ~]$ sudo curl -L https://raw.githubusercontent.com/pyenv/pyenv-installer/master/bin/pyenv-installer | bash
export PATH="/home/www/.pyenv/bin:$PATH"
eval "$(pyenv init -)"
eval "$(pyenv virtualenv-init -)"
4）添加~/.bash_profile
[www@python ~]$ sudo vim /home/www/.bash_profile
export PATH="/home/www/.pyenv/bin:$PATH"
eval "$(pyenv init -)"
eval "$(pyenv virtualenv-init -)"
[www@python ~]$ source /home/www/.bash_profile
二）pyenv简单使用
1）查看可以安装哪里版本
[www@python ~]$ pyenv install -l
2）安装某个版本
[www@python ~]$ pyenv install 3.5.3
第二种方法：
[www@python ~]$ cd .pyenv/
[www@python .pyenv]$ mkdir cache
然后把下载的包（3.5.3），放到cache目录里
然后执行 pyenv install 3.5.3
然后执行 pyenv install 3.6.1
global Set or show the global Python version （影响所有的，一般情况不用）
[www@python ~]$ pyenv version
system (set by /home/www/.pyenv/version)
[www@python ~]$ pyenv global 3.5.3
[www@python ~]$ pyenv version
3.5.3 (set by /home/www/.pyenv/version)
shell Set or show the shell-specific Python version （把当前shell环境改成3.5.3，是会话级别的，一般也不用）
[www@python ~]$ pyenv shell 3.5.3
[www@python ~]$ pyenv version
3.5.3 (set by PYENV_VERSION environment variable)
[www@python ~]$ cd python_syntax/project/
[www@python project]$ ll
total 0
[www@python project]$ pyenv local 3.5.3
[www@python project]$ pyenv version
3.5.3 (set by /home/www/python_syntax/project/.python-version)
[www@python project]$ cd .. （在其他目录下，显示python版本）
[www@python python_syntax]$ pyenv version
system (set by /home/www/.pyenv/version)
[www@python python_syntax]$ cd project/
[www@python project]$ mkdir syntax （在当前目录的子目录下，显示python版本）
[www@python project]$ cd syntax/
[www@python syntax]$ pyenv version
3.5.3 (set by /home/www/python_syntax/project/.python-version)
（在指定目录以及子目录下，使用指定的python版本，其他目录使用别的版本）
使用虚拟环境
Virtualenv插件 plugins/pyenv-virtualenv
创建出一个3.5.3版本的独立空间
[www@python syntax]$ pwd
/home/www/python_syntax/project/syntax
[www@python syntax]$ pyenv virtualenv 3.5.3 yuki353
Requirement already satisfied: setuptools in /home/www/.pyenv/versions/3.5.3/envs/yuki353/lib/python3.5/site-packages
Requirement already satisfied: pip in /home/www/.pyenv/versions/3.5.3/envs/yuki353/lib/python3.5/site-packages
[www@python syntax]$ pyenv versions
* system (set by /home/www/python_syntax/project/.python-version)
3.5.3
3.5.3/envs/yuki353
3.6.1
yuki353
[www@python syntax]$ pyenv local yuki353
(yuki353) [www@python syntax]$
二）pip的安装
[www@python ~]$ mkdir .pip
[www@python ~]$ vim ~/.pip/pip.conf
[global]
index-url=https://mirrors.aliyun.com/pypi/simple/
trusted-host=mirrors.aliyun.com
~
[www@python ~]$ cd python_syntax/project/syntax/
(yuki353) [www@python syntax]$ pip -V
pip 9.0.1 from /home/www/.pyenv/versions/3.5.3/envs/yuki353/lib/python3.5/site-packages (python 3.5)
安装ipython
(yuki353) [www@python syntax]$ pip install ipython
查看安装的包存放位置
[www@python site-packages]$ pwd
/home/www/.pyenv/versions/3.5.3/envs/yuki353/lib/python3.5/site-packages
[www@python site-packages]$ ll|grep pip
drwxrwxr-x. 11 www www 4096 Jan 22 11:49 pip
drwxrwxr-x. 2 www www 155 Jan 22 11:49 pip-9.0.1.dist-info
(yuki353) [www@python syntax]$ pip install jupyter
(yuki353) [www@python syntax]$ jupyter notebook password
Enter password:
Verify password:
[NotebookPasswordApp] Wrote hashed password to /home/www/.jupyter/jupyter_notebook_config.json
(yuki353) [www@python syntax]$ jupyter notebook --ip=0.0.0.0 --no-browser
[I 13:07:42.212 NotebookApp] Writing notebook server cookie secret to /run/user/1000/jupyter/notebook_cookie_secret
[I 13:07:42.947 NotebookApp] Serving notebooks from local directory: /home/www/python_syntax/project/syntax
[I 13:07:42.947 NotebookApp] 0 active kernels
[I 13:07:42.947 NotebookApp] The Jupyter Notebook is running at:
[I 13:07:42.947 NotebookApp] http://0.0.0.0:8888/
[I 13:07:42.947 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).
使用浏览器访问
把安装的包导出来
(yuki353) [www@python syntax]$ pip freeze > /tmp/packages.txt
然后在另一个虚拟环境，把包导入进去
(wangbin353) [www@python syntax]$ pip install -r /tmp/packages.txt
(注意：最好在同一个python版本下导出导入，不建议跨版本（python）使用）
