My requirement is to cancel upload when ever user wishes.
I'm following TransferUtility document to setup and upload video, show progress, retains state even if app is in background. I couldn't find any way to cancel the uploadTask.

```
{
let uploadRequest = AWSS3TransferManagerUploadRequest()
let  transferUtility = AWSS3TransferUtility.default()
var completionHandler : AWSS3TransferUtilityUploadCompletionHandlerBlock?
var uploadTask : AWSTask<AWSS3TransferUtilityUploadTask>?
let expression = AWSS3TransferUtilityUploadExpression()

}

func startUpload() {

uploadTask = transferUtility.uploadFile((uploadRequest?.body)!,
                                   bucket: (uploadRequest?.bucket)!,
                                   key: (uploadRequest?.key)!,
                                   contentType: "video/mov",
                                   expression: expression,
                                   completionHander: completionHandler).continue({ (task) -> AnyObject! in if let error = task.error {
                                    print("Error: \(error.localizedDescription)")
                                    }
                                    if let _ = task.result {

                                    }
                                    return nil;
                                   }) as? AWSTask<AWSS3TransferUtilityUploadTask>

}

```

I want to know which continue block i should use on the task and how to perform something like uploadTask.cancel() just the way we use for TransferManager task.