render() {
    return (
        < >
        <CartHeader />
        <main className='container'>
        <CartItems items={this.state.cart} />
        <Total total={this.state.total} />
        <AddItem products={this.state.products} addItem={this.addItem} />
        </main>
        <CartFooter copyright='2016'/>
      <    />
    );
  }