code: def create_verifier(self, request, credentials):
          
          verifier = {
              'oauth_token': request.resource_owner_key,
              'oauth_verifier': self.token_generator(),
          }
          verifier.update(credentials)
          self.request_validator.save_verifier(
              request.resource_owner_key, verifier, request)
          return verifier
docs: Create and save a new request token.
  
          :param request: OAuthlib request.
          :type request: oauthlib.common.Request
          :param credentials: A dict of extra token credentials.
          :returns: The verifier as a dict.