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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 clear(self) -> None: """ Closes all running containers. """

        logger.debug("clearing all running containers")
        all_uids = [uid for uid in self.__containers.keys()]
        for uid in all_uids:
            try:
                del self[uid]
            except KeyError:
                # Already deleted
                pass
        logger.debug("cleared all running containers")