Hello @Stefan_Hanssen,
There is no single static IP you could add to the whitelist since Datalore runs notebooks on allocated virtual machines in AWS - and such machines are getting disposed & re-created with a new random IP address once the computation is over.
As a solution, you may set up and use in your code some third-party proxy server to access your API.
Hope this helps!
Best regards,
Igor Medovolkin
QA Engineer in Datalore