old_contents: import warnings
  
  
  class Dummy:
      """A class that did nothing.
  
      Examples:
          >>> Dummy()
          <openfisca_core.commons.dummy.Dummy object...
  
      .. deprecated:: 34.7.0
          :class:`.Dummy` has been deprecated and it will be removed in the
          future.
  
      """
  
      def __init__(self) -> None:
          message = [
              "The 'Dummy' class has been deprecated since version 34.7.0,",
              "and will be removed in the future.",
              ]
          warnings.warn(" ".join(message), DeprecationWarning)
  
new_contents: import warnings
  
  
  class Dummy:
      """A class that does nothing."""
  
      def __init__(self) -> None:
          message = [
              "The 'Dummy' class has been deprecated since version 34.7.0,",
              "and will be removed in the future.",
              ]
          warnings.warn(" ".join(message), DeprecationWarning)
          pass
  
subject: Rollback dummy doc