sendToSlack

func sendToSlack() {
        
        let slackUrl = ""
        
        guard let url = URL(string: slackUrl) else {
            print("Error: cannot create URL")
            return
        }
        
        guard let position = lastPosition else {
            print("Error: cannot get last position")
            return
        }
        var urlRequest = URLRequest(url: url)
        urlRequest.httpMethod = "POST"
        let parameters: [String: Any] = ["channel": "",
                                         "username": "Home Office Bot",
                                         "text":"Hey there!]
        
        let jsonParameters: Data
        do {
            jsonParameters = try JSONSerialization.data(withJSONObject: parameters, options: [])
            urlRequest.httpBody = jsonParameters
        } catch {
            print("Error: cannot create JSON from todo")
            return
        }
        
        let session = URLSession.shared
        
        let task = session.dataTask(with: urlRequest) {
            (data, response, error) in
            
            guard error == nil else {
                print(error!)
                return
            }
        }
        task.resume()
    }