code: def value(self, parameter, new_value=None):
          
          for widget_name, values in DEFAULTS.items():
              if parameter in values.keys():
                  widget = getattr(self, widget_name)
                  if new_value is None:
                      return widget.config.value[parameter]
                  else:
                      lg.debug('setting value {0} of {1} to {2}'
                               ''.format(parameter, widget_name, new_value))
                      widget.config.value[parameter] = new_value
docs: This function is a shortcut for any parameter. Instead of calling
          the widget, its config and its values, you can call directly the
          parameter.
  
          Parameters
          ----------
          parameter : str
              name of the parameter of interest
          new_value : str or float, optional
              new value for the parameter
  
          Returns
          -------
          str or float
              if you didn't specify new_value, it returns the current value.
  
          Notes
          -----
          It's important to maintain an organized dict in DEFAULTS which has to
          correspond to the values in the widgets, also the name of the widget.
          DEFAULTS is used like a look-up table.