Virtualenv：没有名为 virtualenvwrapper 的模块，路径错误

Question

为什么在安装 virtualenv 和 virtualenvwrapper 并添加之后

    export WORKON_HOME=$HOME/.virtualenvs
    export PROJECT_HOME=$HOME/Devel
    source /Users/<user>/Library/Enthought/Canopy_64bit/User/bin/virtualenvwrapper.sh

到我的.bash_profile 并运行$ source ~/.bash_profile，我遇到：

    /Library/Frameworks/Python.framework/Versions/7.3/Resources/Python.app/Contents/MacOS/Python: No module named virtualenvwrapper
    virtualenvwrapper.sh: There was a problem running the initialization hooks. 

    If Python could not import the module virtualenvwrapper.hook_loader,
    check that virtualenv has been installed for
    VIRTUALENVWRAPPER_PYTHON=/Library/Frameworks/Python.framework/Versions/Current/bin/python and that PATH is set properly.

?

我的 .bash_profile 看起来像：

    # Setting PATH for EPD_free-7.3-2
    # The orginal version is saved in .bash_profile.pysave
    PATH="/Library/Frameworks/Python.framework/Versions/Current/bin:${PATH}"
    export PATH

    ##
    # Your previous /Users/<user>/.bash_profile file was backed up as /Users/<user>/.bash_profile.macports-saved_2012-11-06_at_11:39:22
    ##

    # MacPorts Installer addition on 2012-11-06_at_11:39:22: adding an appropriate PATH variable for use with MacPorts.
    export PATH=/opt/local/bin:/opt/local/sbin:$PATH
    # Finished adapting your PATH environment variable for use with MacPorts.

    # virtualenvwrapper
    export WORKON_HOME=$HOME/.virtualenvs
    export PROJECT_HOME=$HOME/Devel
    source /Users/<user>/Library/Enthought/Canopy_64bit/User/bin/virtualenvwrapper.sh

    # Added by Canopy installer on 2014-01-26
    # VIRTUAL_ENV_DISABLE_PROMPT can be set to '' to make bashprompt show that Canopy is active, otherwise 1
    VIRTUAL_ENV_DISABLE_PROMPT=1 source /Users/<user>/Library/Enthought/Canopy_64bit/User/bin/activate

Answer 1

所以想通了。事实证明，当我为 python 安装 EPD 时，它添加了前几行：

    # Setting PATH for EPD_free-7.3-2
    # The orginal version is saved in .bash_profile.pysave
    PATH="/Library/Frameworks/Python.framework/Versions/Current/bin:${PATH}"
    export PATH

在我的.bash_profile。将我的 python 更新为 Enthought Canopy 后，我需要将这些行更改为：

   # set path for current python
   PATH="/Users/<user>/Library/Enthought/Canopy_64bit/User/bin:${PATH}"
   export PATH

现在一切正常。然而事实证明，这在一天结束时不会起作用，因为使用 Enthought，它向后移植了 venv，这是 here 所讨论的 python 3 标准。