MacBook-Pro:~ admin$ brew uninstall python3
Uninstalling /usr/local/Cellar/python/3.6.5... (5,102 files, 102.9MB)
MacBook-Pro:~ admin$ python3
-bash: python3: command not found
MacBook-Pro:~ admin$ python
Python 2.7.10 (default, Oct  6 2017, 22:29:07) 
[GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.31)] on darwin
Type "help", "copyright", "credits" or "license" for more information.