python virtual environment configuration and management

• Choose custom installation

• Check to add python to the system environment variables

• At the same time, pip and IDLE interactive tools are installed

• Enter the python command under the cmd command to view python version

C:\Users>python
Python 3.9.0 (tags/v3.9.0:9cf6752, Oct  5 2020, 15:34:40) [MSC v.1927 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>exit()

• Enter pip list under the cmd command and the following command to view pip

  (to return to the drive letter directory)

C:\Users>pip list
Package    Version
---------- -------
pip        20.2.3
setuptools 49.2.1

1. Download and install the virtual environment

C:\Users>pip install virtualenv

• virtualenvwrapper 是一个 virtualenv 虚拟环境的管理库，这个库可以更加方便的管理所有的虚拟环境

C:\Users***>pip install virtualenvwrapper-win

• 更改virtualenvwrapper虚拟环境目录，后面创建的虚拟环境都存储在此目录下

• 在环境变量中新建WORKON_HOME，值为目录。之后创建的虚拟环境将会自动存储在该目录下

3. 虚拟环境的使用

• 创建虚拟环境

  mkvirtualenv 名称

• 激活或切换虚拟环境

  workon my_env

• 退出虚拟环境

  deactivate

• 删除虚拟环境

  rmvirtualenv 名称

• 查看系统所有的虚拟环境

  lsvirtualenv

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