Excuse me, how to support openai family of models in this demo example

Excuse me, how to support openai family of models in this demo example；

Google model, not in service, how to change to openai model

Look at the demo example's configuration to see how the Google model is currently set up. Find where the model provider is specified and replace it with OpenAI's API endpoint and key. Check for any necessary changes to the request format or parameters to match OpenAI's API.

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