Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: Vans Unisex Classic Slip-On (Checkboard) Truewhite/T Skate Shoe 6 Men US / 7.5 Women US
Product description: Hit the skate park in a fresh new pair of Classic Slip-On Checkerboard shoes by Vans The durable canvas and rubber soles make this the perfect skateboarding shoe They are built to take on the wear and tear that comes along with skateboarding The Classic Slip-On Checkerboard is designed for serious skaters and delivers performance and style that Vans is known for
Product feature: Clothing, Shoes & Jewelry, Women, Shoes, Fashion Sneakers
Product brand: Vans
Target attributes: Style
Answer: attribute: style
value: vans
source: product title
attribute: style
value: fashion sneakers
source: product feature
attribute: style
value: vans
source: product description
attribute: style
value: vans
source: product brand