Can't install gensim with pip - python-2.7

Question

I am completely new to Python so I am trying to install gensim but it's not installing. I am using mac.
Below is the output I am getting in terminal:
Requirement already up-to-date: six>=1.5.0 in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/six-1.10.0-py2.7.egg (from gensim)
Requirement already up-to-date: boto>=2.32 in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages (from smart-open>=1.2.1->gensim)
Requirement already up-to-date: bz2file in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages (from smart-open>=1.2.1->gensim)
Requirement already up-to-date: requests in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages (from smart-open>=1.2.1->gensim)
Installing collected packages: numpy, scipy, gensim
Found existing installation: numpy 1.8.0rc1
DEPRECATION: Uninstalling a distutils installed project (numpy) has been deprecated and will be removed in a future version. This is due to the fact that uninstalling a distutils project will only partially uninstall the project.
Uninstalling numpy-1.8.0rc1:
Exception:
Traceback (most recent call last):
File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/basecommand.py", line 215, in main
status = self.run(options, args)
File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/commands/install.py", line 342, in run
prefix=options.prefix_path,
File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/req/req_set.py", line 778, in install
requirement.uninstall(auto_confirm=True)
File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/req/req_install.py", line 754, in uninstall
paths_to_remove.remove(auto_confirm)
File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/req/req_uninstall.py", line 115, in remove
renames(path, new_path)
File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/utils/__init__.py", line 267, in renames
shutil.move(old, new)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 302, in move
copy2(src, real_dst)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 131, in copy2
copystat(src, dst)
File "/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-lCcMmh-uninstall/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/numpy-1.8.0rc1-py2.7.egg-info'

Answer 1

The system python is managed by the OS vendor (Apple, Canonical, etc), and is meant to be used by other OS built-in tools. Having pip mess things up in the vendored python is dangerous. The SIP protection since El Capital makes it harder to break these things, and for good reasons.
Installing a separate python distribution, or
using pip with --user option circumvents the need to require elevated root access. You may still have to add the user's bin folder to the $PATH --
use this:
sudo pip install gensim --user