code: def _get_request_token(self):
          
          if self.request_token is None:
              get_params = {}
              if self.parameters:
                  get_params.update(self.parameters)
              get_params['oauth_callback'] \
                  = self.request.build_absolute_uri(self.callback_url)
              rt_url = self.request_token_url + '?' + urlencode(get_params)
              oauth = OAuth1(self.consumer_key,
                             client_secret=self.consumer_secret)
              response = requests.post(url=rt_url, auth=oauth)
              if response.status_code not in [200, 201]:
                  raise OAuthError(
                      _('Invalid response while obtaining request token'
                        ' from "%s".') % get_token_prefix(
                            self.request_token_url))
              self.request_token = dict(parse_qsl(response.text))
              self.request.session['oauth_%s_request_token' % get_token_prefix(
                  self.request_token_url)] = self.request_token
          return self.request_token
docs: Obtain a temporary request token to authorize an access token and to
          sign the request to obtain the access token