pip和sudo pip的不同pip版本

Question

我使用的是OSX Yosemite和python版本2.7.12 | Anaconda 4.2.0（x86 | u64）

每次我使用pip时，它都显示You are using pip version 8.1.2, however version 9.0.1 is available.You should consider upgrading via the 'pip install --upgrade pip' command.

输入pip -V，得到pip 8.1.2 from /Library/Python/2.7/site-packages (python 2.7)

当我试图使用pip install --upgrade pip升级pip时，收到以下错误消息

Collecting pip
  Using cached pip-9.0.1-py2.py3-none-any.whl
Installing collected packages: pip
  Found existing installation: pip 8.1.2
    Uninstalling pip-8.1.2:

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 317, in run
    prefix=options.prefix_path,
  File "/Library/Python/2.7/site-packages/pip/req/req_set.py", line 736, in install
     requirement.uninstall(auto_confirm=True)
  File "/Library/Python/2.7/site-packages/pip/req/req_install.py", line 742, 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 "/Users/YTQ/anaconda/lib/python2.7/shutil.py", line 303, in move
    os.unlink(src)
OSError: [Errno 13] Permission denied: '/Library/Python/2.7/site-packages/pip-8.1.2.dist-info/DESCRIPTION.rst'

我认为这可能是用户权限问题，所以我使用了sudo pip install --upgrade pip。在

但是，现在只有当我调用sudo pip -V时，它才会返回pip 9.0.1 from /Users/YTQ/anaconda/lib/python2.7/site-packages (python 2.7)。在

{cd2>还是没有。在

此外，当我输入which pip和sudo which pip时，两者都将返回/Users/YTQ/anaconda/bin/pip

我能知道如何解决这个pip升级问题吗？我是否滥用了sudo命令？在