Looking in wikidataquery.py everything is str(), not unicode(). No problem for most of it except when querying STRING["<some string>"]. If you do that and the string happens to contain a non-ascii character:
query = 'CLAIM[31:3305213] AND CLAIM[195:%s] AND STRING[217:"%s"]' % (instid, metadata.get(idField),)
data = wd_query.query(wd_queryset)
File "C:\pywikibot\coredev\pywikibot\data\wikidataquery.py", line 591, in quer
y
fullQueryString = self.getQueryString(q, labels, props)
File "C:\pywikibot\coredev\pywikibot\data\wikidataquery.py", line 481, in getQ
ueryString
qStr = "q=%s" % quote(str(q))
File "C:\pywikibot\coredev\pywikibot\data\wikidataquery.py", line 107, in __st
r__
s = bracketIfQuerySet(self.qs[0])
File "C:\pywikibot\coredev\pywikibot\data\wikidataquery.py", line 105, in brac
ketIfQuerySet
return str(q)
UnicodeEncodeError: 'ascii' codec can't encode character u'\xe3' in position 76:
ordinal not in range(128)
<type 'exceptions.UnicodeEncodeError'>
CRITICAL: Closing network session.
Pywikibot: [ssh] pywikibot-core.git (f0e0d87, g5686, 2015/06/06, 13:11:19, OUTDA
TED)
Release version: 2.0b3
requests version: 2.4.1
cacerts: C:\Python27\lib\site-packages\requests\cacert.pem
certificate test: ok
Python: 2.7.2 (default, Jun 12 2011, 15:08:59) [MSC v.1500 32 bit (Intel)]