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: Polare Real Italian Leather Fashion Multiple Laptop Backpack Travel Bag
Product feature: natural Italian Polished Calf-Skin Leather., fit for 15 inch Laptop., 51(L)*23(W)*30.5(H)cm /20(L)*9(W)*12(H) inch,Net Weight:1.56KG, Tough stitching.Hand Made by professional artisans.a beautifully crafted bag that will only get better with age., Large size,easy to carry your necessary.Inside include laptop padding.Good size for weekend ,vocation trip,business trip., Product Dimensions: 20 x 9 x 12 inches, Shipping Weight: 2.45 pounds, ASIN: B00R7IYH7U, Item model number: 5602271, Date first listed on Amazon: December 19, 2014, Average Customer Review: 5.0 out of 5 stars 1 customer review
Product brand: Polare
Target attributes: Material
Answer: attribute: material
value: leather
source: product title
attribute: material
value: leather
source: product feature