我正在尝试安装一个名为louvain的软件包，我会安装它并安装它：
我检查了它，它已经在dis-packages中了
Requirement already satisfied (use --upgrade to upgrade): louvain in /usr/local/lib/python2.7/dist-packages
Requirement already satisfied (use --upgrade to upgrade): python-igraph>=0.7.0 in /usr/local/lib/python2.7/dist-packages (from louvain)
但是当我尝试import到python时，我收到此错误：
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named louvain
我应该如何从dist-packages导入包？
提前谢谢