The HTTP request to the API sometimes gives an error response, with an HTML body. You're currently calling .json() on the Response object, which gives a JSONDecodeError, and hides the HTTP error which is the real cause.
This pull request asks the requests module to explicitly raise a requests.exceptions.HTTPError instead.
Also, if an error occurs when backing up one board, it carries on with the rest of the boards, and reports all the errors at the end.
The HTTP request to the API sometimes gives an error response, with an HTML body. You're currently calling .json() on the Response object, which gives a JSONDecodeError, and hides the HTTP error which is the real cause.
This pull request asks the requests module to explicitly raise a requests.exceptions.HTTPError instead.
Also, if an error occurs when backing up one board, it carries on with the rest of the boards, and reports all the errors at the end.