How to use the azure-iot-hub.azure.iot.hub.protocol.version.VERSION function in azure-iot-hub

def __init__(self, credentials, base_url=None):

        if credentials is None:
            raise ValueError("Parameter 'credentials' must not be None.")
        if not base_url:
            base_url = "https://fully-qualified-iothubname.azure-devices.net"

        super(IotHubGatewayServiceAPIs20190630Configuration, self).__init__(base_url)

        self.add_user_agent("iothubgatewayserviceapis20190630/{}".format(VERSION))

        self.credentials = credentials