您希望使用gpt-3.5-turbo模型。
ChatGPT API（即GPT-3.5 API）和GPT-3 API之间有三个主要区别：

• API端点
• GPT-3 API：https://api.openai.com/v1/completions
• ChatGPT API：https://api.openai.com/v1/chat/completions
• prompt参数（GPT-3 API）被messages参数（ChatGPT API）替换
• 响应访问
• GPT-3 API：response.choices[0].text.trim()
• ChatGPT API：response.choices[0].message.content.trim()

试试这个：

const getChatResponse = async (incomingChatDiv) => {
    const API_URL = "https://api.openai.com/v1/chat/completions"; /* Changed */
    const pElement = document.createElement("p");

    // Define the properties and data for the API request
    const requestOptions = {
        method: "POST",
        headers: {
            "Content-Type": "application/json",
            "Authorization": `Bearer ${API_KEY}`
        },
        body: JSON.stringify({
            model: "gpt-3.5-turbo",
            messages: [{role: "user", content: `${userText}`}], /* Changed */
            max_tokens: 2048,
            temperature: 0.2,
            n: 1,
            stop: null
        })
    }

    // Send POST request to API, get response and set the reponse as paragraph element text
    try {
        const response = await (await fetch(API_URL, requestOptions)).json();
        pElement.textContent = response.choices[0].message.content.trim(); /* Changed */
    } catch (error) { // Add error class to the paragraph element and set error text
        pElement.classList.add("error");
        pElement.textContent = "Oops! Something went wrong while retrieving the response. Please try again.";
    }

    // Remove the typing animation, append the paragraph element and save the chats to local storage
    incomingChatDiv.querySelector(".typing-animation").remove();
    incomingChatDiv.querySelector(".chat-details").appendChild(pElement);
    localStorage.setItem("all-chats-thedoggybrad", chatContainer.innerHTML);
    chatContainer.scrollTo(0, chatContainer.scrollHeight);
}