The model name in string, defaults to 'gpt-3.5-turbo'. Supported model names:
- gpt-3.5-turbo
- pt-3.5-turbo-0301
***api_key***: *str=None*
The OpenAI API key in string, defaults to None.
***\*\*kwargs***
Other OpenAI parameters such as max_tokens, stream, temperature, etc.
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## Interface
The operator takes a piece of text in string as input.
It returns answer in json.
***\_\_call\_\_(txt)***
**Parameters:**
***messages***: *list*
A list of messages to set up chat.
Must be a list of dictionaries with key value from "system", "question", "answer". For example, [{"question": "a past question?", "answer": "a past answer."}, {"question": "current question?"}]