code: def load_config(self):
          
          expanded_state = self.get_option('expanded_state', None)
          # Sometimes the expanded state option may be truncated in .ini file
          # (for an unknown reason), in this case it would be converted to a
          # string by 'userconfig':
          if is_text_string(expanded_state):
              expanded_state = None
          if expanded_state is not None:
              self.explorer.treewidget.set_expanded_state(expanded_state)
docs: Load configuration: tree widget state