As an administrator of my organization's ArcGIS Online, we monitor credit use used in geoprocessing and storage. We routinely check the amount of storage in content. With the advent of Notebooks in ArcGIS Online comes the Notebook Workspace where files may be stored. These files consume 12 credits per 1 GB stored per month, per user whereas most of the other non-imagery content consumes 1.2 credits per 1 GB stored per month, calculated hourly. While we use the python API to check content storage, I think we are missing the files in the Notebook Workspace. How can I query the Notebook Workspace for the size of the files stored in it for all my users?