我在这里安装了python：

$which -a python
    /usr/local/bin/python
    /usr/bin/python

如果我尝试sudo pip install stevedore,那么它说已经安装了一些警告：

sudo /usr/local/bin/pip install stevedore
The directory '/Users/sidharthnayyar/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo,you may want sudo's -H flag.
The directory '/Users/sidharthnayyar/Library/Caches/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo,you may want sudo's -H flag.
Requirement already satisfied (use --upgrade to upgrade): stevedore in ./Library/Python/2.7/lib/python/site-packages
Requirement already satisfied (use --upgrade to upgrade): pbr>=1.6 in /Library/Python/2.7/site-packages (from stevedore)
Requirement already satisfied (use --upgrade to upgrade): six>=1.9.0 in ./Library/Python/2.7/lib/python/site-packages (from stevedore)

如果我尝试sudo -H pip install stevedore,那么我会收到以下错误：

sudo -H /usr/local/bin/pip install stevedore

Collecting stevedore
    Using cached stevedore-1.18.0-py2.py3-none-any.whl
Requirement already satisfied (use --upgrade to upgrade): pbr>=1.6 in /Library/Python/2.7/site-packages (from stevedore)
Collecting six>=1.9.0 (from stevedore)
    Using cached six-1.10.0-py2.py3-none-any.whl
Installing collected packages: six,stevedore
    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 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 "/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-NOex2K-uninstall/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/six-1.4.1-py2.7.egg-info'

如果我创建一个.bash_profile并放入其中：

export WORKON_HOME=$HOME/.virtualenvs
export PROJECT_HOME=$HOME/Devel
export VIRTUALENVWRAPPER_PYTHON=/usr/local/bin/python
export VIRTUALENVWRAPPER_VIRTUALENV=/usr/local/bin/virtualenv
source /usr/local/bin/virtualenvwrapper.sh

并重新加载终端窗口然后我收到以下错误：

source ~/.bash_profile
Traceback (most recent call last):
    File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/runpy.py",in