from_llm() — langchain Function Reference

Architecture documentation for the from_llm() function in base.py from the langchain codebase.

Function python AgentOrchestration ClassicChains

Entity Profile

AgentOrchestration→ ClassicChains→ from_llm() — langchain Function Reference

Dependency Diagram

graph TD
  2a359647_ad3b_4021_eb9b_23a432e1e2eb["from_llm()"]
  5aa1201d_23fd_f122_acb5_563cb1cc3cb3["BaseQAWithSourcesChain"]
  2a359647_ad3b_4021_eb9b_23a432e1e2eb -->|defined in| 5aa1201d_23fd_f122_acb5_563cb1cc3cb3
  style 2a359647_ad3b_4021_eb9b_23a432e1e2eb fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/langchain/langchain_classic/chains/qa_with_sources/base.py lines 59–86

    def from_llm(
        cls,
        llm: BaseLanguageModel,
        document_prompt: BasePromptTemplate = EXAMPLE_PROMPT,
        question_prompt: BasePromptTemplate = QUESTION_PROMPT,
        combine_prompt: BasePromptTemplate = COMBINE_PROMPT,
        **kwargs: Any,
    ) -> BaseQAWithSourcesChain:
        """Construct the chain from an LLM."""
        llm_question_chain = LLMChain(llm=llm, prompt=question_prompt)
        llm_combine_chain = LLMChain(llm=llm, prompt=combine_prompt)
        combine_results_chain = StuffDocumentsChain(
            llm_chain=llm_combine_chain,
            document_prompt=document_prompt,
            document_variable_name="summaries",
        )
        reduce_documents_chain = ReduceDocumentsChain(
            combine_documents_chain=combine_results_chain,
        )
        combine_documents_chain = MapReduceDocumentsChain(
            llm_chain=llm_question_chain,
            reduce_documents_chain=reduce_documents_chain,
            document_variable_name="context",
        )
        return cls(
            combine_documents_chain=combine_documents_chain,
            **kwargs,
        )