django.fcgi or virtualenv : no module named operator
Since the operator module is part of the standard library, it looks like you have a corrupt Python installation in your virtualenv. The best thing to do would be to simply delete and recreate your virtualenv.
So these are my website informations:

framework : Django
hosting : alwaysdata
python : 2.7
virtualenv is used


The problem :
I have the non explicit 500 error :Internal Server Error
I have not any error log
But :
I found a trail to solve this issue. Indeed when i run manually the django.fcgi, i got this traceback:

Traceback (most recent call last):
  File "public/django.fcgi", line 14, in 
    from django.core.servers.fastcgi import runfastcgi
  File "/home/usr/.virtualenvs/thevirtualenv/lib/python2.7/site-packages/django/core/servers/fastcgi.py", line 17, in 
    from django.utils import importlib
  File "/home/usr/.virtualenvs/thevirtualenv/lib/python2.7/site-packages/django/utils/importlib.py", line 4, in 
    from django.utils import six
  File "/home/usr/.virtualenvs/thevirtualenv/lib/python2.7/site-packages/django/utils/six.py", line 23, in 
    import operator
ImportError: No module named operator


Manipulation(s) which could occur this issue :
I had this issue for 3 week ago, i let it rest too long, so now i can't remember what i have done to bring about this.. But i think it was a dirty virtualenv creation or edition, something like that..
Thanks to bear with my english. 
Does anyone have an Idea about my case?
Attempts to solve this issue:
I just tried to recreate my virtualenv and got this error message :

Traceback (most recent call last):
  File "/home/usr/python/python27/bin/virtualenv", line 5, in 
    from pkg_resources import load_entry_point
zipimport.ZipImportError: can't decompress data; zlib not available