code: def choices(self, changelist):
          
          show_all = self.used_parameters.get(self.parameter_name) == "1"
          return (
              {
                  'display': _('Current Configuration'),
                  'selected': not show_all,
                  'query_string': changelist.get_query_string({}, [self.parameter_name]),
              },
              {
                  'display': _('All (Show History)'),
                  'selected': show_all,
                  'query_string': changelist.get_query_string({self.parameter_name: "1"}, []),
              }
          )
docs: Returns choices ready to be output in the template.