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: Calvin Klein Menton Men US 9.5 Brown Moc Loafer
Product feature: Package Dimensions: 14.2 x 7.8 x 5.4 inches, Shipping Weight: 2.2 pounds, ASIN: B00JH7YS32, Date first listed on Amazon: November 10, 2014, Average Customer Review: 4.0 out of 5 stars 1 customer review
Target attributes: Silhouette
Answer: attribute: silhouette
value: loafer
source: product title