old_contents: from __future__ import unicode_literals
  
  VERSION = ('0', '8', '1')
  __version__ = '.'.join(VERSION)
  
new_contents: from __future__ import unicode_literals
  
  VERSION = ('0', '9', '0', 'dev1')
  __version__ = '.'.join(VERSION)
  
subject: bump version to 0.9.0.dev1