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    Pythonlangchain-classicchainshydebase
    Module●Since v1.0

    base

    Hypothetical Document Embeddings.

    https://arxiv.org/abs/2212.10496

    Attributes

    attribute
    PROMPT_MAP: dict
    attribute
    logger

    Classes

    class
    Chain

    Abstract base class for creating structured sequences of calls to components.

    Chains should be used to encode a sequence of calls to components like models, document retrievers, other chains, etc., and provide a simple interface to this sequence.

    class
    HypotheticalDocumentEmbedder

    Generate hypothetical document for query, and then embed that.

    Based on https://arxiv.org/abs/2212.10496

    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