text: const Item = React.createClass({
      displayName: 'Item',
      getDefaultProps() {
          console.log('get defult props');
          return {
              group: 123
          }
      },
      getInitialState() {
          console.log('get initial state');
          return {
              name: 'leo'
          }
      },
      render() {
          return <div>{this.props.group + this.state.name}</div>
      }
  });
  
  ReactDOM.render(<div>
      <Item/>
      <Item/>
      <Item/>
  </div>, document.getElementById('test'));