text: import React from 'react'
  import WarningBanner from './WarningBanner'
  
  class Page extends React.Component {
      constructor(props) {
        super(props);
        this.state = {showWarning: true};
        this.handleToggleClick = this.handleToggleClick.bind(this);
      }
    
      handleToggleClick() {
        this.setState(state => ({
          showWarning: !state.showWarning
        }));
      }
    
      render() {
        return (
          <div>
            <WarningBanner warn={this.state.showWarning} />
            <button onClick={this.handleToggleClick}>
              {this.state.showWarning ? 'Hide' : 'Show'}
            </button>
          </div>
        );
      }
  }
  
  export default Page