langchain/chains/graph_qa/cypher.py/GraphCypherQAChain/from_llm
class GraphCypherQAChain:    def from_llm(
        cls,
        llm: BaseLanguageModel,
        *,
        qa_prompt: BasePromptTemplate = CYPHER_QA_PROMPT,
        cypher_prompt: BasePromptTemplate = CYPHER_GENERATION_PROMPT,
        **kwargs: Any,
    ) -> GraphCypherQAChain:
        """Initialize from LLM."""
        qa_chain = LLMChain(llm=llm, prompt=qa_prompt)
        cypher_generation_chain = LLMChain(llm=llm, prompt=cypher_prompt)

        return cls(
            qa_chain=qa_chain,
            cypher_generation_chain=cypher_generation_chain,
            **kwargs,
        )