code: def authorized(self, request_token):
          
          verifier = generate_token(length=self.verifier_length[1])
          self.save_verifier(request_token, verifier)
          response = [
              (u'oauth_token', request_token),
              (u'oauth_verifier', verifier)
          ]
          callback = self.get_callback(request_token)
          return redirect(add_params_to_uri(callback, response))
docs: Create a verifier for an user authorized client