来自lxml import etree ImportError undefined symbol：xmlBufContent

Question

安装lxml 3.4.4后，当import lxml一切正常，但from lxml import etree无法正常工作时，错误是：

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: /usr/local/lib/python2.7/site-packages/lxml-3.4.4-py2.7-linux-x86_64.egg/lxml/etree.so: undefined symbol: xmlBufContent

python版本是centos6.5上的python2.7.3。但是当我使用python2.6.6时，from lxml import etree工作正常。我不知道为什么。

顺便说一句，我尝试使用easy_install lxml，它显示：

Searching for lxml
Best match: lxml 3.4.4
Processing lxml-3.4.4-py2.7-linux-x86_64.egg
lxml 3.4.4 is already the active version in easy-install.pth

Using /usr/local/lib/python2.7/site-packages/lxml-3.4.4-py2.7-linux-x86_64.egg
Processing dependencies for lxml
Finished processing dependencies for lxml

有人可以帮忙吗？