old_contents: # See http://www.python.org/dev/peps/pep-0386/ for version numbering, especially NormalizedVersion
  from distutils import version
  version = version.LooseVersion('0.5.9')
  
new_contents: # See http://www.python.org/dev/peps/pep-0386/ for version numbering, especially NormalizedVersion
  from distutils import version
  version = version.LooseVersion('0.5.10-dev')
  
subject: prepare for next development iteration