No module named soundfile

Whenever I try to import soundfile I get the error

ImportError: No module named soundfile

I installed pysoundfile seemingly without trouble:

$ sudo pip install pysoundfileThe directory '~/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.The directory '~/Library/Caches/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.Collecting pysoundfile  Downloading PySoundFile-0.9.0.post1-py2.py3.cp26.cp27.cp32.cp33.cp34.cp35.cp36.pp27.pp32.pp33-none-macosx_10_5_x86_64.macosx_10_6_intel.macosx_10_9_intel.macosx_10_9_x86_64.whl (573kB)    100% |████████████████████████████████| 573kB 430kB/sRequirement already satisfied: cffi>=0.6 in /Library/Python/2.7/site-packages (from pysoundfile)Requirement already satisfied: pycparser in /Library/Python/2.7/site-packages (from cffi>=0.6->pysoundfile)Installing collected packages: pysoundfileSuccessfully installed pysoundfile-0.9.0.post1

so what's causing this problem?