如何在swift 3中创建一个json对象来通过POST api发送？

import Foundation

// 创建一个字典来表示JSON数据
let jsonDict: [String: Any] = [
    "name": "John Doe",
    "age": 30,
    "email": "johndoe@example.com"
]

do {
    // 将字典转换为JSON数据
    let jsonData = try JSONSerialization.data(withJSONObject: jsonDict, options: [])

    // 创建一个URL对象
    let url = URL(string: "https://api.example.com/endpoint")!

    // 创建一个可变的URLRequest对象
    var request = URLRequest(url: url)
    request.httpMethod = "POST"

    // 设置请求头
    request.setValue("application/json", forHTTPHeaderField: "Content-Type")

    // 设置请求体
    request.httpBody = jsonData

    // 发送请求
    let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
        if let error = error {
            print("请求失败：\(error)")
            return
        }

        // 处理响应数据
        if let data = data {
            let responseString = String(data: data, encoding: .utf8)
            print("响应数据：\(responseString ?? "")")
        }
    }

    task.resume()
} catch {
    print("JSON转换失败：\(error)")
}