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: Spirit Moda Nina Women's Strappy Lace Up Ballet Flats D'Orsay Ankle Tie,Tan,10 B(M) US
Product feature: Package Dimensions: 11.1 x 5.8 x 3.8 inches, Shipping Weight: 1 pounds, ASIN: B01CLR64P4, Date first listed on Amazon: April 14, 2016, Average Customer Review: 3.0 out of 5 stars 1 customer review
Product brand: SPIRIT MODA
Target attributes: Silhouette
Answer: attribute: silhouette
value: ballet
source: product title