以下代码集成了 Milvus 和 LangChain：

class VectorStore(ABC):
    """Interface for vector stores."""    @abstractmethoddef add_texts(
        self,
        texts: Iterable[str],
        metadatas: Optional[List[dict]] = None,
kwargs:Any,
    ) ->List[str]:
"""Run more texts through the embeddings and add to the vectorstore."""    @abstractmethoddefsimilarity_search(
        self, query:str, k:int =4,kwargs: Any) -> List[Document]:
        """Return docs most similar to query."""def max_marginal_relevance_search(
        self, query: str, k: int = 4, fetch_k: int = 20) -> List[Document]:
        """Return docs selected using the maximal marginal relevance."""raise NotImpleme