DEFAULT_REFINE_PROMPT_TMPL = "The original question is as follows: {question}\nWe have provided an existing answer: {existing_answer}\nWe have the opportunity to refine the existing answer (
only if needed
) with some more context below.\n------------\n{context_str}\n------------\nGiven the new context, refine the original answer to better answer the question. If the context isn't useful, return the original answer."