def config(self, function):
        """
        Decorator to add a function to the configuration of the Experiment.

        The decorated function is turned into a
        :class:`~sacred.config_scope.ConfigScope` and added to the
        Ingredient/Experiment.

        When the experiment is run, this function will also be executed and
        all json-serializable local variables inside it will end up as entries
        in the configuration of the experiment.
        """
        self.configurations.append(ConfigScope(function))
        return self.configurations[-1]