予期しないforの繰り返しが行われてしまいます。

前提・実現したいこと

期待する結果としては
uploadAction(fileName)、search関数、その結果をもとにself.uploadを処理して次の繰り返しをpictureDicの要素数実行して欲しいのですが
現状は
uploadAction(fileName)、search関数、２回めのuploadAction(fileName)、search関数　・・・（pictureDicの要素数繰り返す）、uploadFile関数内のif let ID = folderID以降の処理がおこなわれてself.upload処理をpictureDicの要素数繰り返してしまいます。

発生している問題・

    @IBAction func finishButtonClick(_ sender: Any) {
        for (fileName, UIimage) in pictureDic{
            saveImageToDocumentLocal(name: fileName, image: UIimage)
            sleep(3)
            uploadAction(fileName)
            
        }
        let nextViewController = finishViewController()
        UIApplication.shared.keyWindow?.rootViewController = nextViewController
        UIApplication.shared.keyWindow?.rootViewController?.dismiss(animated: false, completion: nil)
    }

    func uploadAction(_ file: String) {
        print(file)
        if let documentsDir = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last {
            let testFilePath = documentsDir.appendingPathComponent(file).path
           drive?.uploadFile("20200204", filePath: testFilePath, MIMEType: "image/png") { (fileID, error) in
                print("Upload file ID: (fileID); Error: (error?.localizedDescription)")
            }
        }
    }

   public func uploadFile(_ folderName: String, filePath: String, MIMEType: String, onCompleted: ((String?, Error?) -> ())?) {
        search(folderName) { (folderID, error) in
        if let ID = folderID {
                self.upload(ID, path: filePath, MIMEType: MIMEType, onCompleted: onCompleted)
        } else {
                self.createFolder(folderName, onCompleted: { (folderID, error) in
                    guard let ID = folderID else {
                        onCompleted?(nil, error)
                        return
                    }
                    self.upload(ID, path: filePath, MIMEType: MIMEType, onCompleted: onCompleted)
                })
            }
        }
    }

    public func search(_ fileName: String, onCompleted: @escaping (String?, Error?) -> ()) {
        let query = GTLRDriveQuery_FilesList.query()
        query.pageSize = 1
        query.q = "name contains '(fileName)'"
        service.executeQuery(query) { (ticket, results, error) in
            onCompleted((results as? GTLRDrive_FileList)?.files?.first?.identifier, error)
            print("search ID: (String(describing: results)); Error: (String(describing: error))")
        }
    }