def METHOD_NAME(self, request, credentials):
    """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.
    """
    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