This question shows how to use pip for different python versions. However, I have the same version of python installed in two different paths. Let's not ask why, if I remove one, things break.
$ /usr/local/bin/python -c "import sys; print sys.version"
2.7.10 (default, Jun 10 2015, 19:42:47)
[GCC 4.2.1 Compatible Apple LLVM 6.1.0 (clang-602.0.53)]
$ /usr/bin/python -c "import sys; print sys.version"
2.7.10 (default, Jul 14 2015, 19:46:27)
[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.39)]
pip seems to install packages to /usr/local/bin/python.
How do I install a package to /usr/bin/python?
I'm on OS X, Yosemite (10.10).