安装Let’s Encrypt遇到错误

Creating virtual environment...
Traceback (most recent call last):
File "/usr/bin/virtualenv", line 2, in
import virtualenv
ImportError: No module named virtualenv

需要操作：

yum install python-virtualenv

如果之后还是不行请使用：

yum install python-setuptools python-devel
easy_install virtualenv