code: def put_values(self):
          
          for value_name, widget in self.index.items():
              widget.set_value(self.value[value_name])
              widget.connect(self.set_modified)
docs: Put values to the GUI.
  
          Notes
          -----
          In addition, when one small widget has been changed, it calls
          set_modified, so that we know that the preference widget was modified.