old_contents: from __future__ import absolute_import
  
  from .version_info import PY3
  
  if PY3:
      from StringIO import *
  else:
      try:
          from cStringIO import *
      except ImportError:
          from StringIO import *
  
new_contents: from __future__ import absolute_import
  
  from .version_info import PY3
  
  if PY3:
      from io.StringIO import *
  else:
      try:
          from cStringIO import *
      except ImportError:
          from StringIO import *
  
subject: Fix StringIO on Python 3