code: def OnInsertCols(self, event):
          
  
          bbox = self.grid.selection.get_bbox()
  
          if bbox is None or bbox[1][1] is None:
              # Insert rows at cursor
              ins_point = self.grid.actions.cursor[1] - 1
              no_cols = 1
          else:
              # Insert at right edge of bounding box
              ins_point = bbox[0][1] - 1
              no_cols = self._get_no_rowscols(bbox)[1]
  
          with undo.group(_("Insert columns")):
              self.grid.actions.insert_cols(ins_point, no_cols)
  
          self.grid.GetTable().ResetView()
  
          # Update the default sized cell sizes
          self.grid.actions.zoom()
  
          event.Skip()
docs: Inserts the maximum of 1 and the number of selected columns