第1章 创建虚拟环境

以下操作在mac系统上执行，Linux系统类似，而Windows的路径有点区别，主要是activate文件是在Scripts下，同时需要先执行set-executionpolicy remotesigned之后，再执行./.venv/Scripts/Activate.ps1

使用命令python -m venv .venv创建虚拟环境

huangsiyangdeiMac:projects huangsiyang$ python -m venv .venv

 

在刚才创建的虚拟环境路径下，使用命令source bin/activate激活虚拟环境：

huangsiyangdeiMac:projects huangsiyang$ source .venv/bin/activate

终端变成如下：

(.venv) huangsiyangdeiMac:projects huangsiyang$ 

 

执行pip3 --version，可以看到路径发生了变化，如：

(.venv) huangsiyangdeiMac:projects huangsiyang$ pip --version

pip 19.2.3 from /Users/huangsiyang/projects/.venv/lib/python3.7/site-packages/pip (python 3.7)

 

升级pip版本，如：

(.venv) huangsiyangdeiMac:projects huangsiyang$ pip install --upgrade pip

Collecting pip

  Downloading https://files.pythonhosted.org/packages/4d/16/0a14ca596f30316efd412a60bdfac02a7259bf8673d4d917dc60b9a21812/pip-22.0.4-py3-none-any.whl (2.1MB)

     |████████████████████████████████| 2.1MB 679kB/s 

Installing collected packages: pip

  Found existing installation: pip 19.2.3

    Uninstalling pip-19.2.3:

      Successfully uninstalled pip-19.2.3

Successfully installed pip-22.0.4

 

再查看pip版本，如：

(.venv) huangsiyangdeiMac:projects huangsiyang$ pip --version

pip 22.0.4 from /Users/huangsiyang/projects/.venv/lib/python3.7/site-packages/pip (python 3.7)

 

离开虚拟环境，如：

(.venv) huangsiyangdeiMac:projects huangsiyang$ deactivate 

huangsiyangdeiMac:projects huangsiyang$ 

 

再次查看pip版本，如：

huangsiyangdeiMac:projects huangsiyang$ pip --version

pip 19.3.1 from /usr/local/lib/python3.7/site-packages/pip (python 3.7)