def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def __init__(self, auth_provider):
        super(SnapshotsClientJSON, self).__init__(auth_provider)

        self.service = CONF.volume.catalog_type
        self.build_interval = CONF.volume.build_interval
        self.build_timeout = CONF.volume.build_timeout