使用chatglm2-6b模型报错。请问什么原因？怎么修改

运行web_demo.py成功了，但是在进行提问回答的时候报错了
To create a public link, set share=True in launch().
F:\anaconda\envs\lm\lib\site-packages\gradio\helpers.py:818: UserWarning: Using the update method is deprecated. Simply return a new object instead, e.g. return gr.Textbox(...) instead of return gr.update(...).
warnings.warn(
F:\anaconda\envs\lm\lib\site-packages\gradio\components\textbox.py:163: UserWarning: Using the update method is deprecated. Simply return a new object instead, e.g. return gr.Textbox(...) instead of return gr.Textbox.update(...).
warnings.warn(
Traceback (most recent call last):
File "F:\anaconda\envs\lm\lib\site-packages\gradio\queueing.py", line 406, in call_prediction
output = await route_utils.call_process_api(
File "F:\anaconda\envs\lm\lib\site-packages\gradio\route_utils.py", line 226, in call_process_api
output = await app.get_blocks().process_api(
File "F:\anaconda\envs\lm\lib\site-packages\gradio\blocks.py", line 1554, in process_api
result = await self.call_function(
File "F:\anaconda\envs\lm\lib\site-packages\gradio\blocks.py", line 1206, in call_function
prediction = await utils.async_iteration(iterator)
File "F:\anaconda\envs\lm\lib\site-packages\gradio\utils.py", line 517, in async_iteration
return await iterator.anext()
File "F:\anaconda\envs\lm\lib\site-packages\gradio\utils.py", line 510, in anext
return await anyio.to_thread.run_sync(
File "F:\anaconda\envs\lm\lib\site-packages\anyio\to_thread.py", line 33, in run_sync
return await get_asynclib().run_sync_in_worker_thread(
File "F:\anaconda\envs\lm\lib\site-packages\anyio_backends_asyncio.py", line 877, in run_sync_in_worker_thread
return await future
File "F:\anaconda\envs\lm\lib\site-packages\anyio_backends_asyncio.py", line 807, in run
result = context.run(func, args)
File "F:\anaconda\envs\lm\lib\site-packages\gradio\utils.py", line 493, in run_sync_iterator_async
return next(iterator)
File "F:\anaconda\envs\lm\lib\site-packages\gradio\utils.py", line 647, in gen_wrapper
yield from f(args, **kwargs)
File "F:\code\ChatGLM2-6B-main\ChatGLM2-6B-main\web_demo.py", line 66, in predict
for response, history, past_key_values in model.stream_chat(tokenizer, input, history, past_key_value=past_key_values,
ValueError: not enough values to unpack (expected 3, got 2)