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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save(self) -> None: """ Saves the contents of the source manager to disk. """

        logger.info('saving registry to: %s', self.__registry_fn)
        d = [s.to_dict() for s in self]

        os.makedirs(self.__path, exist_ok=True)
        with open(self.__registry_fn, 'w') as f:
            yaml.dump(d, f, indent=2, default_flow_style=False)
        logger.info('saved registry to: %s', self.__registry_fn)