```py

custom_qa_prompt = (
    "We have provided context information below. \n"
    "---------------------\n"
    "{context_str}"
    "\n---------------------\n"
    "Given this information, please answer the question: {query_str}\n"
)
custom_qa_template = PromptTemplate(custom_qa_prompt)
response_synthesizer = get_response_synthesizer(
    llm=LLM_INSTANCES[model], text_qa_template=custom_qa_template
)