     }
     
     @objc public class func requestRequestToken(session: Session, xAuthMode: xAuthMode = .None, callback: String = "oob", handler: @escaping (String?, String?, Swift.Error?) -> Void) {
-        guard let url = URL.twitterOAuthURL(endpoint: "request_token") else {
-            handler(nil, nil, Error.Unknown)
-            return
-        }
+        let url = URL.twitterOAuthURL(endpoint: "request_token")!
         
         let httpMethod = "POST"
         

                    
                    handler(token, tokenSecret, userID, screenName, nil)
                }
                catch let error as NSError {
                    handler(nil, nil, -1, nil, error)
                }
                catch {
                    handler(nil, nil, -1, nil, Error.Unknown)
                }
            })
            task.resume()
        }
        catch let error as NSError {
            handler(nil, nil, -1, nil, error)
        }
        catch {
            handler(nil, nil, -1, nil, Error.Unknown)
        }
    }
    

                    
                    handler(token, tokenSecret, nil)
                }
                catch let error {
                    handler(nil, nil, error)
                }
            })
            task.resume()
        }
        catch let error {
            handler(nil, nil, error)
        }
    }
    
    @objc public class func requestAccessToken(session: Session, requestToken: String, requestTokenSecret: String, xAuthMode: xAuthMode = .None, xAuthUsername: String? = nil, xAuthPassword: String? = nil, oauthVerifier: String? = nil, handler: @escaping (String?, String?, Int64, String?, Swift.Error?) -> Void) {
        let url = URL.twitterOAuthURL(endpoint: "access_token")!
        
        let httpMethod = "POST"
        
