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    Pythonlangchain-classicretrieversdocument_compressorschain_extract
    Module●Since v1.0

    chain_extract

    DocumentFilter that uses an LLM chain to extract the relevant parts of documents.

    Attributes

    attribute
    prompt_template: str

    Functions

    function
    default_get_input

    Return the compression chain input.

    Classes

    class
    NoOutputParser

    Parse outputs that could return a null string of some sort.

    class
    LLMChainExtractor

    LLM Chain Extractor.

    Document compressor that uses an LLM chain to extract the relevant parts of documents.

    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")
    View source on GitHub