来自swift前端的POST请求问题

let url = URL(string: "https://example.com/api")!
var request = URLRequest(url: url)
request.httpMethod = "POST"

let parameters = ["username": "john", "password": "secret"]
request.httpBody = try? JSONSerialization.data(withJSONObject: parameters)

let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
    if let error = error {
        print("Error: \(error)")
        return
    }
    
    if let data = data {
        let responseString = String(data: data, encoding: .utf8)
        print("Response: \(responseString)")
    }
}

task.resume()