def __call__(self, server_descriptions):
        secondaries = secondary_with_tags_server_selector(
            self.tag_sets,
            server_descriptions)

        if secondaries:
            return secondaries
        else:
            return writable_server_selector(server_descriptions)
Return matching ServerDescriptions from a list.
dataset/ETHPy150Open mongodb/mongo-python-driver/pymongo/read_preferences.py/SecondaryPreferred.__call__