Ah, good point.
You certainly end up with a table and tree, both referencing the data held in the table and both having 4 rows (in this case) but yes, each table row becomes a tree column 0 element.
My take on this was as stated in the title - map a table to a tree - I don't know whether the parent child relationship between table row elements is actually that important. It makes a great intellectual exercise though, well solved!
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