def build_prompt(question: str, context: str) -> str:
    return (
        "You are an expert assistant. Answer the USER question using only the "
        "CONTEXT provided. If the context is insufficient say 'I don't know.'.\n\n"
        f"### CONTEXT\n{context}\n\n"
        f"### USER QUESTION\n{question}\n\n### ASSISTANT ANSWER\n"
    )