Mac环境下配置Python3（解决报错）

Mac下是自带Python的，不过版本较低Python 2.7.10，要安装下最新的Python3。
1.打开终端，通过Homebrew查找下python3

$ brew search python3

==> Formulae
boost-python3                                                python@3
python3                                                      homebrew/linuxbrew-core/boost-python3

2.找到python3，安装：

$ brew install python3

安装提示有个Error
Error: Xcode alone is not sufficient on Mojave.
Install the Command Line Tools:
  xcode-select --install

3.解决Error，在终端执行命令安装the Command Line Tools

$ xcode-select --install

此时会弹出提示安装the Command Line Tools，我们按照提示进行下载安装即可，安装完毕继续执行

$ brew install python3

4.又发现新的报错：

==> Pouring python-3.7.4_1.mojave.bottle.1.tar.gz
Error: An unexpected error occurred during the `brew link` step
The formula built, but is not symlinked into /usr/local
Permission denied @ dir_s_mkdir - /usr/local/Frameworks
Error: Permission denied @ dir_s_mkdir - /usr/local/Frameworks

发现/usr/local/下没有路径/usr/local/Frameworks
需要新建该路径，并修改权限
解决：

$ sudo mkdir /usr/local/Frameworks
$ sudo chown $(whoami):admin /usr/local/Frameworks
$ brew link python

5.完成

$ python3 -V
Python 3.7.4