I\'m using python 3.4 in a virtual environment:
(af)[root@domain backend]# pip --version pip 7.1.0 from /home/af/af-stage/backend/.ves/af/lib/python3.4/sit
You just need to use yum install python-lxml. Of course, lxml module depend on libxml2 libxslt libxml2-devel libxslt-devel.
yum install python-lxml