Mac 下安装Python3.5出现“python3-3.5.0 already installed, it's just not linked”错误
1.在Mac下用Homebrew安装Python3.5(Mac自带的Python是2.7)brewinstallpython32.安装完成之后发现出错了Error:Anunexpectederroroccurredduringthe`brewlink`stepTheformulabuilt,butisnotsymlinkedinto/usr/localPermissiondenied-/usr/l