@staticmethod
def rollback_action(args, kwargs, was_interrupted, result=None):
    """
        This static method shall determine and undo all the changes made by a previous
        :meth:`process_action` call.
        If :meth:`process_action` was interrupted by a crash or an exception, *was_interrupted*
        is True, and *result* is None. Else, result is the value (if any) which was returned by the
        meth:`process_action` call - this might be an appreciable hint in some circumstances.
        In any case, args and kwargs are the list and dict which contain the arguments with which
        :meth:`process_action` was called.
        In case of trouble preventing the rollback, this method shall raise an exception.
        No return value is expected.
        """
    raise NotImplementedError()
