关于通义千问的WEB_demo和API参数

from gradio_client import Client

client = Client("http://127.0.0.1:7860/")
result = client.predict(
"Howdy!", # str in 'Input' Textbox component
"null", # str (filepath to JSON file) in 'Qwen-7B-Chat' Chatbot component
fn_index=0
)
print(result)

这里面的这个"null"，就是JSON文件是哪一个？