requests: URL has an invalid label.

requests v2.12.0

>>> import requests
>>> requests.get('http://vluki_develop_624_solr:8983/solr/vluki')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/dist-packages/requests/api.py", line 70, in get
    return request('get', url, params=params, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/requests/api.py", line 56, in request
    return session.request(method=method, url=url, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/requests/sessions.py", line 474, in request
    prep = self.prepare_request(req)
  File "/usr/local/lib/python2.7/dist-packages/requests/sessions.py", line 407, in prepare_request
    hooks=merge_hooks(request.hooks, self.hooks),
  File "/usr/local/lib/python2.7/dist-packages/requests/models.py", line 302, in prepare
    self.prepare_url(url, params)
  File "/usr/local/lib/python2.7/dist-packages/requests/models.py", line 372, in prepare_url
    raise InvalidURL('URL has an invalid label.')
requests.exceptions.InvalidURL: URL has an invalid label.