from langchain_core.runnables import RunnableLambda, RunnablePassthrough from langchain_core.prompts import ChatPromptTemplate from langchain_core.output_parsers import StrOutputParser from langchain_core.messages import HumanMessage from langchain_community.llms import HuggingFaceEndpoint from langchain_community.embeddings import HuggingFaceEmbeddings llm = HuggingFaceEndpoint(repo_id="HuggingFaceH4/zephyr-7b-beta", max_new_tokens=1024) embed_model = HuggingFaceEmbeddings(model_name="sentence-transformers/all-mpnet-base-v2") prompt = ChatPromptTemplate.from_template("Answer the question: {question}") chain = prompt | llm | StrOutputParser() def build_graph(): return chain