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The URL, systemKey, and token this endpoint requires are obtained differently than others. To get those, do the following:
Click the Select project drop-down at the top of the IoT Core UI.
Click the Edit icon (pencil) next to the desired project.
Go to the SERVICE ACCOUNTS tab.
If a service account already exists, select it and choose DOWNLOAD CREDENTIALS. If a service account does not exist, create it and select DOWNLOAD CREDENTIALS.
A JSON file will be downloaded to your local machine. Open the file with an editor. Use the file’s systemKey, token, and URL as needed below.
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