private function createExampleProduct($offer_id)
 {
     $product = new Google_Service_ShoppingContent_Product();
     $product->setOfferId($offer_id);
     $product->setTitle('A Tale of Two Cities');
     $product->setDescription('A classic novel about the French Revolution');
     $product->setLink('http://my-book-shop.com/tale-of-two-cities.html');
     $product->setImageLink('http://my-book-shop.com/tale-of-two-cities.jpg');
     $product->setContentLanguage('en');
     $product->setTargetCountry('US');
     $product->setChannel('online');
     $product->setAvailability('in stock');
     $product->setCondition('new');
     $product->setGoogleProductCategory('Media > Books');
     $product->setGtin('9780007350896');
     $price = new Google_Service_ShoppingContent_Price();
     $price->setValue('2.50');
     $price->setCurrency('USD');
     $product->setPrice($price);
     $shipping_price = new Google_Service_ShoppingContent_Price();
     $shipping_price->setValue('0.99');
     $shipping_price->setCurrency('USD');
     $shipping = new Google_Service_ShoppingContent_ProductShipping();
     $shipping->setPrice($shipping_price);
     $shipping->setCountry('US');
     $shipping->setService('Standard shipping');
     $product->setShipping(array($shipping));
     $shipping_weight = new Google_Service_ShoppingContent_ProductShippingWeight();
     $shipping_weight->setValue(200);
     $shipping_weight->setUnit('grams');
     $product->setShippingWeight($shipping_weight);
     return $product;
 }