Use Homebrew to Install both Python 2 and 3 on Mac

Posted on | Visitors:

起因

公司项目使用Python2.7，自己LeetCode刷题想使用Python3

背景

macOS中自带了Python2.7，只需要安装Python3

安装Python3

一定要用 brew 安装 Python3 (不然很有可能会和系统的Python库有冲突)

1
$ brew install python3

上面的语句会自动安装 pip3
网上文章上都说用brew安装Python3会自带pip3的安装
但是不知什么原因,我使用brew安装完Python3后并没有pip3

安装pip3

下载文件

1
2
$ wget https://bootstrap.pypa.io/get-pip.py
$ python3 get-pip.py

创建软连接 到/usr/local/bin

1
2
3
4
5
6
7
8
$ ln -s /usr/local/Cellar/python/3.7.2_1/Frameworks/Python.framework/Versions/3.7/bin/pip3 /usr/local/bin/
$ which pip3
/usr/local/bin/pip3
$ cd /usr/local/Cellar/python/3.7.2_1/Frameworks/Python.framework/Versions/3.7/bin/
$ diff pip pip3
$
$ diff pip pip3.7
$

说明pip、pip3、pip3.7三个文件相同

安装virtualenv

1
$ sudo pip3 install virtualenv

1
$ ln -s /usr/local/Cellar/python/3.7.2_1/Frameworks/Python.framework/Versions/3.7/bin/virtualenv /usr/local/bin
1
2
$ cd ~/lixiang2017_code/leetcode
$ virtualenv --no-site-packages venv_py3

1
$ sudo virtualenv --no-site-packages venv_py3

activate

deactivate