code: def change_exteditor(self):
          
          path, valid = QInputDialog.getText(self, _('External editor'),
                            _('External editor executable path:'),
                            QLineEdit.Normal,
                            self.get_option('external_editor/path'))
          if valid:
              self.set_option('external_editor/path', to_text_string(path))
docs: Change external editor path