如何获取OkHttp 4.x的UserAgent？

implementation 'com.squareup.okhttp3:okhttp:4.x.x'

OkHttpClient client = new OkHttpClient();

Request request = new Request.Builder()
        .url("https://www.example.com")
        .build();

Call call = client.newCall(request);

call.enqueue(new Callback() {
    @Override
    public void onResponse(Call call, Response response) throws IOException {
        // 在这里获取到Response对象，并处理你所需的数据
        String userAgent = response.header("User-Agent");
        // 这里的userAgent即为OkHttp的User-Agent
    }

    @Override
    public void onFailure(Call call, IOException e) {
        // 请求失败处理
    }
});

Request request = new Request.Builder()
        .url("https://www.example.com")
        .header("User-Agent", "自定义User-Agent")
        .build();