pip: six issue when installing package

The error

When you try to install a python project using pip and you are using macOS and you get the error:

Installing collected packages: six, python-dateutil, docutils, botocore, pyasn1, rsa, colorama, awscli
  Found existing installation: six 1.4.1
    DEPRECATION: Uninstalling a distutils installed project (six) 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 six-1.4.1:
Exception:
Traceback (most recent call last):
  File "/Library/Python/2.7/site-packages/pip/basecommand.py", line 211, in main
    status = self.run(options, args)
  File "/Library/Python/2.7/site-packages/pip/commands/install.py", line 311, in run
    root=options.root_path,
  File "/Library/Python/2.7/site-packages/pip/req/req_set.py", line 640, in install
    requirement.uninstall(auto_confirm=True)
  File "/Library/Python/2.7/site-packages/pip/req/req_install.py", line 716, in uninstall
    paths_to_remove.remove(auto_confirm)
  File "/Library/Python/2.7/site-packages/pip/req/req_uninstall.py", line 125, in remove
    renames(path, new_path)
  File "/Library/Python/2.7/site-packages/pip/utils/__init__.py", line 315, 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: '/var/folders/6t/h404bjcd5tb_4q86tpv_251rv_0h0j/T/pip-sYsqDS-uninstall/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/six-1.4.1-py2.7.egg-info'

Solution

MacOS ships with six 1.4.1 installed already and when it attempts to uninstall it doesn't have permission to do so because System Integrity Protection doesn't allow even root to modify those directories. Try to install the six using the command:

pip install --ignore-installed six