如何在 Mac OS 上使用 pip 安装 PIL?

我正在尝试使用以下命令安装 PIL(Python 成像库):

I am trying to install PIL (the Python Imaging Library) using the command:

sudo pip install pil

但我收到以下消息:

Downloading/unpacking PIL
  You are installing a potentially insecure and unverifiable file. Future versions of pip will default to disallowing insecure files.
  Downloading PIL-1.1.7.tar.gz (506kB): 506kB downloaded
  Running setup.py egg_info for package PIL
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    
Installing collected packages: PIL
  Running setup.py install for PIL
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py
    --- using frameworks at /System/Library/Frameworks
    building '_imaging' extension
    clang -fno-strict-aliasing -fno-common -dynamic -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -mno-fused-madd -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE -arch i386 -arch x86_64 -pipe -IlibImaging -I/System/Library/Frameworks/Python.framework/Versions/2.7/include -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c _imaging.c -o build/temp.macosx-10.8-intel-2.7/_imaging.o
    unable to execute clang: No such file or directory
    error: command 'clang' failed with exit status 1
    Complete output from command /usr/bin/python -c "import setuptools;__file__='/private/tmp/pip_build_root/PIL/setup.py';exec(compile(open(__file__).read().replace('
', '
'), __file__, 'exec'))" install --record /tmp/pip-AYrxVD-record/install-record.txt --single-version-externally-managed:
    WARNING: '' not a valid package name; please use only.-separated package names in setup.py

running install

running build

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.
.
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copying PIL/XVThumbImagePlugin.py -> build/lib.macosx-10.8-intel-2.7

running build_ext

--- using frameworks at /System/Library/Frameworks

building '_imaging' extension

creating build/temp.macosx-10.8-intel-2.7

creating build/temp.macosx-10.8-intel-2.7/libImaging

clang -fno-strict-aliasing -fno-common -dynamic -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -mno-fused-madd -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE -arch i386 -arch x86_64 -pipe -IlibImaging -I/System/Library/Frameworks/Python.framework/Versions/2.7/include -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c _imaging.c -o build/temp.macosx-10.8-intel-2.7/_imaging.o

unable to execute clang: No such file or directory

error: command 'clang' failed with exit status 1

----------------------------------------
Cleaning up…

你能帮我安装PIL吗?