Most of the documentaion is outdated, and I haven't been able to find any clean exaamples. Hoping this helps someone.
Products and Customers scripts are working for now. Hoping to support more in the future. Make a pull request or raise an issue if you need help.
You need api keys and tokens. You can set those up here. https://devportal.3dcart.com
This saves the first 100 raw info as a json file. You can adjust or filter as needed by the URL.
This saves all your customer's info as a json file. You will need pagination if you are extending 1000+