MAC 下升级 setuptools 失败

已经是 root 用户了，不知道为啥还报 Operation not permitted

MacOS 10.12.3 ， Python 2.7.10

root# pip install -U pip setuptools
Requirement already up-to-date: pip in /Library/Python/2.7/site-packages
Collecting setuptools
  Using cached setuptools-34.3.0-py2.py3-none-any.whl
Collecting packaging>=16.8 (from setuptools)
  Using cached packaging-16.8-py2.py3-none-any.whl
Collecting appdirs>=1.4.0 (from setuptools)
  Using cached appdirs-1.4.1-py2.py3-none-any.whl
Collecting six>=1.6.0 (from setuptools)
  Using cached six-1.10.0-py2.py3-none-any.whl
Collecting pyparsing (from packaging>=16.8->setuptools)
  Using cached pyparsing-2.1.10-py2.py3-none-any.whl
Installing collected packages: six, pyparsing, packaging, appdirs, setuptools
  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 215, in main
    status = self.run(options, args)
  File "/Library/Python/2.7/site-packages/pip/commands/install.py", line 342, in run
    prefix=options.prefix_path,
  File "/Library/Python/2.7/site-packages/pip/req/req_set.py", line 778, in install
    requirement.uninstall(auto_confirm=True)
  File "/Library/Python/2.7/site-packages/pip/req/req_install.py", line 754, in uninstall
    paths_to_remove.remove(auto_confirm)
  File "/Library/Python/2.7/site-packages/pip/req/req_uninstall.py", line 115, in remove
    renames(path, new_path)
  File "/Library/Python/2.7/site-packages/pip/utils/__init__.py", line 267, 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-fZIEx5-uninstall/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/six-1.4.1-py2.7.egg-info'