python - “sudo pip install 6”后出现“No module named Six”错误

Question

当我运行 python 代码时，调试说No module named six. 我去终端安装。我有：

Requirement already satisfied (use --upgrade to upgrade):  six in /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python

然后我再次运行 python，仍然得到No module named six. 如何处理？