Python版本管理工具pyenv使用小结

安装`brew`

1	/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

安装`pyenv`

1	brew install pyenv

把`pyenv`加入环境变量

如果使用的终端是bash，则编辑~/.bashrc，如果使用的终端是zsh，则编辑~/.zshrc，在该文件的最开头加入语句：

1
2

# pyenv init -  pyenv初始化，把pyenv加入环境变量，使其生效，否则pyenv命令无法使用，pyenv命令是pyenv的核心命令，用于安装、卸载、查看、切换不同版本的python，pyenv的其他命令都是围绕这个命令展开的
eval "$(pyenv init -)"

`pyenv`常用基本命令

pyenv install --list                            # List all available versions
pyenv install <version>                         # install python
pyenv global <version>                          # 全局设置python版本为指定版本
pyenv global 2.7.14 3.6.4                       # 指定多个python版本为全局版本，有顺序
pyenv local <version>                           # 设置当前路径下python版本为指定版本
pyenv shell <version>                           # 设置当前shell窗口使用的python版本为指定版本
pyenv versions                                  # 列举所有版本的python，打``*``的为当前指定的全局版本
pyenv version                                   # 列举已经安装的版本

使用`virtualenv`创建`Python`虚拟环境

这个命令只需要一个参数，即虚拟环境的名字。创建完虚拟环境后，当前文件夹会出现一个子文件夹，名字就是上述命令中指定的参数，与虚拟环境相关的文件都保存在这个子文件夹中。按照惯例，一般虚拟环境会被命名为venv：

$ virtualenv venv
New python executable in /Users/taoyi/git_projects/Python_Training/flasky/venv/bin/python2.7
Also creating executable in /Users/taoyi/git_projects/Python_Training/flasky/venv/bin/python
Installing setuptools, pip, wheel...done.

（Linux或Mac OS X用户）激活当前虚拟环境：

1	source venv/bin/activate

虚拟环境被激活后，其中Python解释器的路径就被添加进PATH中，但这种改变不是永久性的，它只会影响当前的命令行会话。为了提醒你已经激活了虚拟环境，激活虚拟环境的命令会修改命令行提示符，加入环境名：

1
2
3

$ python -V
Python 2.7.14
(venv)

如果想回到全局Python解析器中，可以再命令行提示符下输入deactivate。

使用`virtualenv`创建指定版本的`Python`的虚拟环境

1	virtualenv -p /Users/taoyi/.pyenv/versions/3.6.5/bin/python py3env

-p：指定指定版本的python的绝对路径
py3env：创建的虚拟环境的名称

Ubuntu环境下，pyenv安装python失败，解决方法

报错信息：

# ubuntu @ VM-4-14-ubuntu in /usr/bin [16:24:51]
$ pyenv install 3.11.3
WARNING: Please make sure you remove any previous custom paths from your /home/ubuntu/.pydistutils.cfg file.
Downloading Python-3.11.3.tar.xz...
-> https://www.python.org/ftp/python/3.11.3/Python-3.11.3.tar.xz
Installing Python-3.11.3...
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/ubuntu/.pyenv/versions/3.11.3/lib/python3.11/curses/__init__.py", line 13, in <module>
    from _curses import *
ModuleNotFoundError: No module named '_curses'
WARNING: The Python curses extension was not compiled. Missing the ncurses lib?
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/ubuntu/.pyenv/versions/3.11.3/lib/python3.11/ctypes/__init__.py", line 8, in <module>
    from _ctypes import Union, Structure, Array
ModuleNotFoundError: No module named '_ctypes'
WARNING: The Python ctypes extension was not compiled. Missing the libffi lib?
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ModuleNotFoundError: No module named 'readline'
WARNING: The Python readline extension was not compiled. Missing the GNU readline lib?
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/ubuntu/.pyenv/versions/3.11.3/lib/python3.11/ssl.py", line 100, in <module>
    import _ssl             # if we can't import it, let the error propagate
    ^^^^^^^^^^^
ModuleNotFoundError: No module named '_ssl'
ERROR: The Python ssl extension was not compiled. Missing the OpenSSL lib?

Please consult to the Wiki page to fix the problem.
https://github.com/pyenv/pyenv/wiki/Common-build-problems


BUILD FAILED (Ubuntu 22.04 using python-build 20180424)
...

`ModuleNotFoundError: No module named '_curses'`报错

1 2	ModuleNotFoundError: No module named '_curses' WARNING: The Python curses extension was not compiled. Missing the ncurses lib?

解决

1	sudo apt-get install libncurses-dev

`ModuleNotFoundError: No module named '_ctypes'`报错

1 2	ModuleNotFoundError: No module named '_ctypes' WARNING: The Python ctypes extension was not compiled. Missing the libffi lib?

解决

1	sudo apt-get install libffi-dev

`ModuleNotFoundError: No module named 'readline'`报错

1 2	ModuleNotFoundError: No module named 'readline' WARNING: The Python readline extension was not compiled. Missing the GNU readline lib?

解决

1	sudo apt-get install libreadline-dev

`ModuleNotFoundError: No module named '_ssl'`报错

1 2	ModuleNotFoundError: No module named '_ssl' ERROR: The Python ssl extension was not compiled. Missing the OpenSSL lib?

解决

1	sudo apt-get install libssl-dev

安装brew

安装pyenv

把pyenv加入环境变量

pyenv常用基本命令

使用virtualenv创建Python虚拟环境

使用virtualenv创建指定版本的Python的虚拟环境