Wikipedia urls with special characters result in an error

[Tomin1]

I get this error:

18:29 <Willie> KeyError: u'extract' (file 
"/usr/local/lib/python2.7/dist-packages/willie/modules/wikipedia.py", line 83, 
               in mw_snippet)

When I give Wille an url like this: http://en.wikipedia.org/wiki/Troll_%28Internet%29
The reason are the percent encoded characters in the url. To fix this I made some modifications to my wikipedia.py but they are not compatible with Python 2, I think, and might not be the proper way to solve this problem. To see the code I wrote see this commit: https://github.com/Tomin1/willie/commit/019848763594da688ae6ed79e180373d8c472694 Anyway I think more time and thinking about this problem is needed and this fix is not final and should not be merged.

Some more information:
exceptions.log:

Signature: KeyError: u'extract' (file "/usr/local/lib/python2.7/dist-packages/willie/modules/wikipedia.py", line 83, in mw_snippet)
from Tomi at 2015-01-28 18:29:59.907542. Message was: http://en.wikipedia.org/wiki/Troll_%28Internet%29
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/willie/bot.py", line 634, in call
    exit_code = func(willie, trigger)
  File "/usr/local/lib/python2.7/dist-packages/willie/modules/wikipedia.py", line 93, in mw_info
    say_snippet(bot, match.group(1), match.group(2), show_url=False)
  File "/usr/local/lib/python2.7/dist-packages/willie/modules/wikipedia.py", line 60, in say_snippet
    snippet = mw_snippet(server, query)
  File "/usr/local/lib/python2.7/dist-packages/willie/modules/wikipedia.py", line 83, in mw_snippet
    return snippet['extract']
KeyError: u'extract'

Willie v. 5.0.0
Raspbian (Debian wheezy) on Raspberry Pi, installed with pip.