Returns a human readable settings representation for logging purposes.

def _settings_str(self):
        """Returns a human readable settings representation for logging purposes."""
        settings = "Automatically save changes: {}, " \
            "Show tray icon: {}, " \
            "Allow keyboard navigation: {}, " \
            "Sort by usage count: {}, " \
            "Enable undo using backspace: {}, " \
            "Tray icon theme: {}".format(
               self.autosave_checkbox.isChecked(),
               self.show_tray_checkbox.isChecked(),
               self.allow_kb_nav_checkbox.isChecked(),
               self.sort_by_usage_checkbox.isChecked(),
               self.enable_undo_checkbox.isChecked(),
               self.system_tray_icon_theme_combobox.currentData(Qt.UserRole)
            )
        return settings