code: def highlight_channels(self, l, selected_chan):
          
          for row in range(l.count()):
              item = l.item(row)
              if item.text() in selected_chan:
                  item.setSelected(True)
              else:
                  item.setSelected(False)
docs: Highlight channels in the list of channels.
  
          Parameters
          ----------
          selected_chan : list of str
              channels to indicate as selected.