安装python3的时候就是输入python3死活没有反应的解决方法

ERROR：The `brew link` step did not complete successfully The formula built, but is not symlinked into /usr/local Could not symlink lib/pkgconfig/python-3.6.pc

brew link python3

brew doctor

Warning: You have unlinked kegs in your Cellar
Leaving kegs unlinked can lead to build-trouble and cause brews that depend on
those kegs to fail to run properly once built. Run `brew link` on these:
 pcre
 python3
 xz

brew link xz

Linking /usr/local/Cellar/xz/5.2.3... 
Error: Could not symlink lib/pkgconfig/liblzma.pc
/usr/local/lib/pkgconfig is not writable.

sudo chown -R $USER /usr/local/lib/pkgconfig 

brew link xz
Linking /usr/local/Cellar/xz/5.2.3... 53 symlinks created

python3
Python 3.6.2 (default, Jul 17 2017, 16:44:45) 
[GCC 4.2.1 Compatible Apple LLVM 8.1.0 (clang-802.0.42)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
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