code: def set_visible_graphs(self, visible_graph_list=None):
          
          if visible_graph_list is None:
              visible_graph_list = self.visible_graph_list
  
          vline = urwid.AttrWrap(urwid.SolidFill(u'|'), 'line')
  
          graph_vector_column_list = []
          for state, graph, sub_title in zip(visible_graph_list,
                                             self.bar_graph_vector,
                                             self.sub_title_list):
              if state:
                  text_w = urwid.Text(sub_title, align='center')
                  sub_title_widget = urwid.ListBox([text_w])
                  graph_a = [('fixed', 1, sub_title_widget),
                             ('weight', 1, graph)]
                  graph_and_title = urwid.Pile(graph_a)
                  graph_vector_column_list.append(('weight', 1, graph_and_title))
                  graph_vector_column_list.append(('fixed', 1, vline))
  
          # if all sub graph are disabled
          if not graph_vector_column_list:
              self.visible_graph_list = visible_graph_list
              self.original_widget = urwid.Pile([])
              return
  
          # remove the last vertical line separator
          graph_vector_column_list.pop()
  
          y_label_a = ('weight', 1, urwid.Columns(graph_vector_column_list))
          y_label_and_graphs = [self.y_label,
                                y_label_a]
          column_w = urwid.Columns(y_label_and_graphs, dividechars=1)
          y_label_and_graphs_widget = urwid.WidgetPlaceholder(column_w)
  
          init_widget = urwid.Pile([('fixed', 1, self.title),
                                    ('weight', 1, y_label_and_graphs_widget)])
  
          self.visible_graph_list = visible_graph_list
          self.original_widget = init_widget
docs: Show a column of the graph selected for display