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: Jessica Simpson Kids' Lolita-K
Product description: Lazer cut ballet flat with square toe
Product feature: 100% Synthetic, Imported, Synthetic sole, Slip oon ballet with lazer cuts, Shipping Information: View shipping rates and policies, ASIN: B0142MR540, Item model number: Lolita - K, Date first listed on Amazon: February 4, 2016, Domestic Shipping: Currently, item can be shipped only within the U.S. and to APO/FPO addresses. For APO/FPO shipments, please check with the manufacturer regarding warranty and support issues., International Shipping: This item is not eligible for international shipping. Learn More, Average Customer Review: 3.9 out of 5 stars 7 customer reviews
Product price: $49.98
Target attributes: Silhouette
Answer: attribute: silhouette
value: ballet
source: product feature
attribute: silhouette
value: ballet
source: product description
attribute: silhouette
value: flat
source: product description