get text on image for handwriting

.swift

    func fetchOCRText () {
        let manager = CognitiveServices()
        
        let ocrImage = image!.crop(rect: ocrImageRect!)
        
        manager.retrieveTextOnImage(ocrImage) {
            operationURL, error in
            
            if #available(iOS 10.0, *) {
                
                guard let _ = operationURL else {
                    print("Seems like the network call failed - did you enter the Computer Vision Key in CognitiveServices.swift in line 69? :)")
                    return
                }
                
                let when = DispatchTime.now() + 2
                DispatchQueue.main.asyncAfter(deadline: when) {
                    
                    manager.retrieveResultForOcrOperation(operationURL!, completion: {
                        results, error -> (Void) in
                        
                        if let theResult = results {
                            var ocrText = ""
                            for result in theResult {
                                ocrText = "\(ocrText) \(result)"
                            }
                            self.addLabelForOCR(text: ocrText)
                        } else {
                            self.addLabelForOCR(text: "No text for writing")
                        }
                        
                    })
                }
            }
        }
    }