How do I access packages installed by `pip --user`?

I realized I had an outdated numpy version:

$ pythonPython 2.7.10 (default, Oct 23 2015, 18:05:06)[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.5)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> import numpy as np>>> np.version.full_version'1.8.0rc1'

I sought to update it, but I couldn't install on the entire machine for some reason:

$ sudo pip install -U numpyPassword:Downloading/unpacking numpy from https://pypi.python.org/packages/dd/9f/cd0ec9c50e4ed8650901ad4afde164e5252b6182a9e0c7bff5f8b4441960/numpy-1.11.1.zip#md5=5caa3428b24aaa07e72c79d115140e46  Downloading numpy-1.11.1.zip (4.7MB): 4.7MB downloaded  ...  Found existing installation: numpy 1.8.0rc1    Uninstalling numpy:Cleaning up...Exception:Traceback (most recent call last):  File "/Library/Python/2.7/site-packages/pip-1.4.1-py2.7.egg/pip/basecommand.py", line 134, in main    status = self.run(options, args)  File "/Library/Python/2.7/site-packages/pip-1.4.1-py2.7.egg/pip/commands/install.py", line 241, in run    requirement_set.install(install_options, global_options, root=options.root_path)  File "/Library/Python/2.7/site-packages/pip-1.4.1-py2.7.egg/pip/req.py", line 1294, in install    requirement.uninstall(auto_confirm=True)  File "/Library/Python/2.7/site-packages/pip-1.4.1-py2.7.egg/pip/req.py", line 525, in uninstall    paths_to_remove.remove(auto_confirm)  File "/Library/Python/2.7/site-packages/pip-1.4.1-py2.7.egg/pip/req.py", line 1639, in remove    renames(path, new_path)  File "/Library/Python/2.7/site-packages/pip-1.4.1-py2.7.egg/pip/util.py", line 294, in renames    shutil.move(old, new)  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 302, in move    copy2(src, real_dst)  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 131, in copy2    copystat(src, dst)  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 103, in copystat    os.chflags(dst, st.st_flags)OSError: [Errno 1] Operation not permitted: '/tmp/pip-fajcj_-uninstall/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/numpy-1.8.0rc1-py2.7.egg-info'Storing complete log in /Users/csaftoiu/Library/Logs/pip.log

Ok, I'll just install to --user then:

$ pip install -U --user numpy...Successfully installed numpy

But the version is not updated!

$ pythonPython 2.7.10 (default, Oct 23 2015, 18:05:06)[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.5)] on darwinType "help", "copyright", "credits" or "license" for more information.>>> import numpy as np>>> np.version.full_version'1.8.0rc1'

Where did the installed version go?