Non-fatal error during demo docker configuration

[ajslaghu]

While using:
To use the base setup, copy this docker-compose file to a directory: https://raw.githubusercontent.com/Data2Semantics/brwsr/master/docker-compose.yml.
Run docker-compose up.
This will run brwsr at http://localhost:5000 with the DBPedia SPARQL endpoint.

Errors are thrown in the docker console:
qber_1 | Traceback (most recent call last):
qber_1 | File "/usr/local/lib/python2.7/threading.py", line 801, in __bootstrap_inner
qber_1 | self.run()
qber_1 | File "/usr/local/lib/python2.7/threading.py", line 754, in run
qber_1 | self.__target(*self.__args, **self.__kwargs)
qber_1 | File "/usr/local/brwsr/app/client.py", line 230, in predicate_specific_sparql
qber_1 | res = sparql.query().convert()
qber_1 | File "/usr/local/lib/python2.7/site-packages/SPARQLWrapper/Wrapper.py", line 567, in query
qber_1 | return QueryResult(self._query())
qber_1 | File "/usr/local/lib/python2.7/site-packages/SPARQLWrapper/Wrapper.py", line 537, in _query
qber_1 | response = urlopener(request)
qber_1 | File "/usr/local/lib/python2.7/urllib2.py", line 154, in urlopen
qber_1 | return opener.open(url, data, timeout)
qber_1 | File "/usr/local/lib/python2.7/urllib2.py", line 429, in open
qber_1 | response = self._open(req, data)
qber_1 | File "/usr/local/lib/python2.7/urllib2.py", line 447, in _open
qber_1 | '_open', req)
qber_1 | File "/usr/local/lib/python2.7/urllib2.py", line 407, in _call_chain
qber_1 | result = func(*args)
qber_1 | File "/usr/local/lib/python2.7/urllib2.py", line 1228, in http_open
qber_1 | return self.do_open(httplib.HTTPConnection, req)
qber_1 | File "/usr/local/lib/python2.7/urllib2.py", line 1198, in do_open
qber_1 | raise URLError(err)
qber_1 | URLError: <urlopen error [Errno -2] Name or service not known>