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    Pythonlangchain-classicchainsroutermulti_retrieval_qaMultiRetrievalQAChainfrom_retrievers
    Method●Since v1.0

    from_retrievers

    Create a multi retrieval qa chain from an LLM and a default chain.

    Copy
    from_retrievers(
      cls,
      llm: BaseLanguageModel,
      retriever_infos: list[dict[str, Any]],
      default_retriever: BaseRetriever | None = None,
      default_prompt: PromptTemplate | None = None,
      default_chain: Chain | None = None,
      *,
      default_chain_llm: BaseLanguageModel | None = None,
      **kwargs: Any = {}
    ) -> MultiRetrievalQAChain

    Parameters

    NameTypeDescription
    llm*BaseLanguageModel

    The language model to use.

    retriever_infos*list[dict[str, Any]]

    Dictionaries containing retriever information.

    default_retrieverBaseRetriever | None
    Default:None

    Optional default retriever to use if no default chain is provided.

    default_promptPromptTemplate | None
    Default:None

    Optional prompt template to use for the default retriever.

    default_chainChain | None
    Default:None

    Optional default chain to use when router doesn't map input to one of the destinations.

    default_chain_llmBaseLanguageModel | None
    Default:None

    Optional language model to use if no default chain and no default retriever are provided.

    **kwargsAny
    Default:{}

    Additional keyword arguments to pass to the chain.

    View source on GitHub