Querying spreadsheet values

If I define a spreadsheet trait on a piece, is it possible to query its values somehow?

For example, to display the content of row 5, colum 3 with a text label or use that value in a Calculated Property etc etc.

I can’t figure out what the individual cell values could be called by… As a matter of fact, even the spreadsheet trait itself is left unnamed. However, those values are stored somewhere…