langchain_elasticsearch 0.2.2# cache ElasticsearchCache ElasticsearchEmbeddingsCache chat_history ElasticsearchChatMessageHistory client create_elasticsearch_client embeddings ElasticsearchEmbeddings EmbeddingServiceAdapter retrievers ElasticsearchRetriever vectorstores ElasticsearchStore ApproxRetrievalStrategy BM25RetrievalStrategy BaseRetrievalStrategy ExactRetrievalStrategy SparseRetrievalStrategy