langchain/retrievers/self_query/weaviate.py/WeaviateTranslator/_map_func
class WeaviateTranslator:    def _map_func(self, func: Union[Operator, Comparator]) -> str:
        # https://weaviate.io/developers/weaviate/api/graphql/filters
        map_dict = {Operator.AND: "And", Operator.OR: "Or", Comparator.EQ: "Equal"}
        return map_dict[func]