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: Yin Yang Couple Belly Button Ring
Product description: 316L Surgical steel curved barbell in the standard size 14 gauge 3/8". The top 5mm ball and bottom 8mm ball each have a black gemstone. The Yin Yang couple are made of .925 sterling silver, nickel free. One couple is in a black color, the other in the natural sterling silver color.
Product feature: ASIN: B000VEHDF0, Date first listed on Amazon: August 24, 2007, Average Customer Review: 4.0 out of 5 stars 1 customer review
Product brand: Pierce this 2
Target attributes: Design
Answer: attribute: design
value: belly button ring
source: product title
attribute: design
value: barbell
source: product description