w web application server.

        :param request_validator: An implementation of
                                  oauthlib.oauth2.RequestValidator.
        :param token_expires_in: An int or a function to generate a token
                                 expiration offset (in seconds) given a
                                 oauthlib.common.Request object.
        :param token_generator: A function to generate a token from a request.
        :param refresh_token_generator: A function to generate a token from a
                                        request for the refresh token.
        :param kwargs: Extra parameters to pass to authorization-,
                       token-, resource-, and revocation-endpoint constructors.
        r