安装PyObjc时出错:命令'/ usr/bin/clang'失败

我一直在研究python脚本,首先使用Psychopy编译器,它已经包含了我所需要的所有内容,但现在我需要让它更加独立.我有脚本在Windows计算机上工作,但我也希望它在OSX中工作.

该脚本使用pyglet,我按照这篇文章来安装它.但是,当我到达安装PyObjc的最新步骤时,我有以下错误:

40 warnings and 1 error generated.

error: command '/usr/bin/clang' failed with exit status 1

----------------------------------------
Cleaning up...
Command /Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python -c "import setuptools, tokenize;__file__='/private/var/folders/fk/1plt8wj53_d183pv59scmg4m0000gn/T/pip_build_JL/pyobjc-core/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /var/folders/fk/1plt8wj53_d183pv59scmg4m0000gn/T/pip-HfEjaW-record/install-record.txt --single-version-externally-managed --compile failed with error code 1 in /private/var/folders/fk/1plt8wj53_d183pv59scmg4m0000gn/T/pip_build_JL/pyobjc-core
Storing debug log for failure in /Users/JL/.pip/pip.log

为什么会出现此错误？我该怎么做才能解决它？