As a sidenote, iirc someone mentioned HubSpot used Javascript to build everything themselves as well, hence I (As a HS developer) prefer to use Javascript instead of Python in Custom Code blocks.
The comments above are amazing info, and I think this could be the /thread but as a final note, if you want to start with using the API, download Postman, look up a couple REST API tutorials / search around in the community, and do a couple of examples with the API like, “let me create a contact”, “Let me update that contact”, “Create a Company”, “Associate them” etc.
As the API strucute is sometimes a bit different then it would be in the User Interface, it’s good to learnt he difference between the 2.
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