Function extendSelectionAbove

extendSelectionAbove(notebook, toTop?): void
Extend the selection to the cell above.
Parameters
- notebook: Notebook
  The target notebook widget.
- toTop: boolean = false
  If true, denotes selection to extend to the top.
  
  Notes
  This is a no-op if the first cell is the active cell. The new cell will be activated.
Returns void
- Defined in packages/notebook/src/actions.tsx:1118