AFNetworking的uploadTask怎么写？

Question

github文档上的众多示例代码中，有一段上传的：

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];

AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

NSURL *URL = [NSURL URLWithString:@"http://example.com/upload"];

NSURLRequest *request = [NSURLRequest requestWithURL:URL];

NSURL *filePath = [NSURL fileURLWithPath:@"file://path/to/image.png"];

NSURLSessionUploadTask *uploadTask = [manager uploadTaskWithRequest:request fromFile:filePath progress:nil completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (error) {
        NSLog(@"Error: %@", error);
    } else {
        NSLog(@"Success: %@ %@", response, responseObject);
    }
}];
[uploadTask resume];

我在swift项目引入afn3.1.0，照着上面的示例写的代码，运行会报错：
GET method must not have a body

{Error Domain=kCFErrorDomainCFNetwork Code=-1103 "(null)"}}

Optional(Error Domain=NSURLErrorDomain Code=-1103 "resource exceeds maximum size"

  let manager = AFHTTPSessionManager(sessionConfiguration: config)
        
  let req = URLRequest(url: URL(string: "http://127.0.0.1:8080/upload.php")!)
        
  let fileURL = Bundle.main.url(forResource: "g.jpg", withExtension: nil)
        
 (manager.uploadTask(with: req, fromFile: fileURL!) { (progress) in
            print(progress)
 } completionHandler: { (response, some, err) in
            if (err != nil){ print(err);return }
            print(response)
            print(some)
 }).resume()