old_contents: """Jupyter theme version info"""
  
  # Copyright (c) Jupyter Development Team.
  # Distributed under the terms of the Modified BSD License.
  
  version_info = (
      0,
      3,
      0,
  )
  
  __version__ = '.'.join(map(str, version_info))
  
new_contents: """Jupyter theme version info"""
  
  # Copyright (c) Jupyter Development Team.
  # Distributed under the terms of the Modified BSD License.
  
  version_info = (
      0,
      4,
      0,
  )
  
  __version__ = '.'.join(map(str, version_info))
  
subject: bump to version v0.4.0