# 在macOS上安装Python3和virtualenv环境

## 安装python3

* 可以通过[Homebrew](http://brew.sh/)安装

```
xcode-select --install
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

echo "export PATH=/usr/local/bin:$PATH" >> ~/.bash_profile
```

```
brew install python3
```

* 或者直接通过[Python官方网站](https://www.python.org)下载安装 `macOS 64-bit installer`

> 官方Python 3安装会在用户目录`~/.bash_profile`添加：

```
PATH="/Library/Frameworks/Python.framework/Versions/3.7/bin:${PATH}"
export PATH
```

所以，默认就可以找到 `python3`。注意，这个解析器也要在[VS Code](https://github.com/huataihuang/cloud-atlas-draft/tree/6f3204fffc11cf006abd394631e2598d98b415c3/develop/mac/vscode/README.md)中设置

## 安装virtualenv

```
pip3 install virtualenv
```

> 可能需要翻墙才能安装

并且可能提示升级pip版本

```
pip3 install --upgrade pip
```

```
$ pip --version
pip 18.1 from /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip (python 3.7)
```

```
$ python3 --version
Python 3.7.0

$ which python3
/Library/Frameworks/Python.framework/Versions/3.7/bin/python3
```

## 参考

* [Install Python 3 on Mac OS X and use virtualenv and virtualenvwrapper](http://www.marinamele.com/2014/07/install-python3-on-mac-os-x-and-use-virtualenv-and-virtualenvwrapper.html)
* [Python3 Virtualenv Setup](https://gist.github.com/pandafulmanda/730a9355e088a9970b18275cb9eadef3)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://huataihuang.gitbook.io/cloud-atlas-draft/develop/python/startup/install_python_3_and_virtualenv_on_macos.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.