'X11/Xlib.h' file not found 에러 발생시 해결 방법
Cpython make 중 에러 발생
ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Tk.framework/Versions/8.5/Headers/X11 /usr/local/include/X11
reference: https://github.com/pinax/pinax-project-teams/issues/1