Dame el código para conectar con la API de gpt-4 con todos los detalles

fun main(args: Array<String>) {
    val url = URL("https://api.openAI.com")
    
    val conn = url.openConnection() as HttpURLConnection
    conn.requestMethod = "POST"
    conn.setRequestProperty("Authorization", "Bearer sk-KQMR6kl6Mt8Yi8aAW2r")
    conn.setRequestProperty("Content-Type", "application/json")
    conn.doOutput = true
    
    val wr = OutputStreamWriter(conn.outputStream)
    wr.write(json)
    wr.flush()
    wr.close()
    
    val status = conn.responseCode
    
    if (status == 200) {
        val reader = BufferedReader(InputStreamReader(conn.inputStream))
        val sb = StringBuilder()
        var line: String? = reader.readLine()
        
        while (line != null) {
            sb.append(line)
            line = reader.readLine()
        }
        reader.close()