new_contents: from __future__ import absolute_import, print_function
  import sys
  
  from future.utils import PY2
  from future.tests.base import unittest
  
  
  class ImportHttplibTest(unittest.TestCase):
      def test_issue_159(self):
          """
          The latest version of urllib3 (as of 2015-07-25)
          uses http.client.HTTPMessage, which isn't normally
          exported on Py2 through __all__ in httplib.py.
          """
          from http.client import HTTPMessage
          if PY2:
              import mimetools
              assert issubclass(HTTPMessage, mimetools.Message)
          else:
              import email.message
              assert issubclass(HTTPMessage, email.message.Message)
  
  
  if __name__ == '__main__':
      unittest.main()
  
subject: Add test highlighting urllib3 missing HTTPMessage import from http.client (issue #159)