The target notebook widget.
the mode of adding cells: 'below' (default) adds cells below the active cell, 'belowSelected' adds cells below all selected cells, 'above' adds cells above the active cell, and 'replace' removes the currently selected cells and adds cells in their place.
The last pasted cell becomes the active cell. This is a no-op if there is no cell data on the clipboard. This action can be undone.
Paste cells from the application clipboard.