Python error message "Incompatible library version" libxml and etree.so

Question

Update 2:

the main problem turned out to be a different one from what I had thought it was, and asked for help here. I moved the new question to a new post:

Install custom python package in virtualenv

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Update: ok, so I screwed up my non-virtualenv by accident. The non-virtualenv (normal bash) I could easily fix by removing the manually installed (via pip) lxml and running

conda install lxml --force

But for some reason, that doesn't work in the virtualenv. There, running

    conda install lxml --force

works without error message, but when I run python and simply say

>>> import lxml
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named lxml

Any suggestions??

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old message:

I'm trying to use virtualenv for my python flask application. The python code runs perfectly fine without the virtualenv.

I've installed the packages I need in the virtualenv, but I after installing lxml via

pip install lxml
Installing collected packages: lxml
Successfully installed lxml-3.6.0

I get the following error message when running my code:

  File "/Users/XXX/xxx/flask-aws/lib/python2.7/site-packages/docx-0.2.4-py2.7.egg/docx.py", line 17, in <module>
from lxml import etree

ImportError: dlopen(/Users/XXX/xxx/flask-aws/lib/python2.7/site-packages/lxml/etree.so, 2): Library not loaded: libxml2.2.dylib
  Referenced from: /Users/XXX/xxx/flask-aws/lib/python2.7/site-packages/lxml/etree.so

  Reason: Incompatible library version: etree.so requires version 12.0.0 or later, but libxml2.2.dylib provides version 10.0.0

I have seen other people report similar problems at stackoverflow, and one guy remarked that the problem might related to the virtualenv, but there was no solution.

Once again: The python code runs perfectly fine without virtualenv! But inside virtualenv, I can't get it to work.

I'm using Anaconda Python 2.7 on a Mac.

I'd appreciate any help guys!

Answer 1

I had the same error and stumbled upon this link, after searching for the incompatible library error "libxml2.2.dylib provides version 10.0.0"

Installing libxml2 that worked for me:

brew install libxml2 
brew link --force libxml2