old_contents: __version__ = '0.0.12'
  
  from .base import not_set, ConfigItem, ConfigManager
  from .exceptions import UnknownConfigItem, ConfigValueNotSet, UnsupportedOperation
  
new_contents: __version__ = '0.0.13'
  
  from .base import not_set, ConfigItem, ConfigManager
  from .exceptions import UnknownConfigItem, ConfigValueNotSet, UnsupportedOperation
  
subject: Bump version