Remove ``key`` from dictionary.

        :param key: Key to remove from Zookeeper.
        :type key: string

def depersist(self, key):
        """
        Remove ``key`` from dictionary.

        :param key: Key to remove from Zookeeper.
        :type key: string
        """
        self.connection.retry(self.connection.delete, self.__path_of(key))
        self.__increment_last_updated()