1 read in the react-the source code of the bootstrap.But I feel very confused, the open value is how change?The following code

dropdown.js
Dropdown.propTypes = propTypes;
Dropdown.defaultProps = defaultProps;
setBsClass ("dropdown", Dropdown);
const UncontrolledDropdown = uncontrollable (Dropdown, {open:" onToggle"});
UncontrolledDropdown.Toggle = DropdownToggle;
UncontrolledDropdown.Menu = DropdownMenu;
export default UncontrolledDropdown;