<http://schema.org/position>
"3"^^<http://www.w3.org/2001/XMLSchema#integer>
<http://product.rakuten.co.jp/product/Logicool+G430/a19e9889a3d4f35dc9c7ae84bd63c734/summary/1/?sc=2&l2-id=pdt_filter_asuraku>