[Tips] Mac Python 降级 3.7 -> 3.6

针对3.6升级到3.7出现的问题

Step 1 查看本地3.6版本

brew info python

$> brew info python
python: stable 3.7.2 (bottled), HEAD
Interpreted, interactive, object-oriented programming language
https://www.python.org/
/usr/local/Cellar/python/3.6.3 (3,690 files, 57.5MB)
  Poured from bottle on 2017-11-22 at 10:41:58
/usr/local/Cellar/python/3.7.2 (8,437 files, 118MB) *
  Built from source on 2019-01-09 at 18:35:11
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/python.rb

Step 2 切换版本

brew switch python 3.6.3