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    Pythonlangchain-classicchainscombine_documentsmap_rerank
    Module●Since v1.0

    map_rerank

    Combining documents by mapping a chain over them first, then reranking results.

    Classes

    class
    BaseCombineDocumentsChain

    Base interface for chains combining documents.

    Subclasses of this chain deal with combining documents in a variety of ways. This base class exists to add some uniformity in the interface these types of chains should expose. Namely, they expect an input key related to the documents to use (default input_documents), and then also expose a method to calculate the length of a prompt from documents (useful for outside callers to use to determine whether it's safe to pass a list of documents into this chain or whether that will be longer than the context length).

    class
    RegexParser

    Parse the output of an LLM call using a regex.

    deprecatedclass
    LLMChain

    Chain to run queries against LLMs.

    This class is deprecated. See below for an example implementation using LangChain runnables:

    from langchain_core.output_parsers import StrOutputParser
    from langchain_core.prompts import PromptTemplate
    from langchain_openai import OpenAI
    
    prompt_template = "Tell me a {adjective} joke"
    prompt = PromptTemplate(input_variables=["adjective"], template=prompt_template)
    model = OpenAI()
    chain = prompt | model | StrOutputParser()
    
    chain.invoke("your adjective here")
    deprecatedclass
    MapRerankDocumentsChain

    Combining documents by mapping a chain over them, then reranking results.

    This algorithm calls an LLMChain on each input document. The LLMChain is expected to have an OutputParser that parses the result into both an answer (answer_key) and a score (rank_key). The answer with the highest score is then returned.

    View source on GitHub