＆＃34;没有名为six＆＃34; ＆＃34; sudo pip install six＆＃34;

Question

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

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。 怎么处理呢？