code: def on_unicode_checkbox(self, w=None, state=False):
          
          logging.debug("unicode State is %s", state)
  
          # Update the controller to the state of the checkbox
          self.controller.smooth_graph_mode = state
          if state:
              self.hline = urwid.AttrWrap(
                  urwid.SolidFill(u'\N{LOWER ONE QUARTER BLOCK}'), 'line')
          else:
              self.hline = urwid.AttrWrap(urwid.SolidFill(u' '), 'line')
  
          for graph in self.graphs.values():
              graph.set_smooth_colors(state)
  
          self.show_graphs()
docs: Enable smooth edges if utf-8 is supported