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: Adrianna Papell Women's Halter Gown with Taffeta Skirt
Product feature: 100% Polyester, Imported, Zipper closure, Hand Wash, Sleeveless taffeta gown with front slit and beaded bodice, Racerback with concealed zipper, Package Dimensions: 1 x 1 x 1 inches, Shipping Weight: 1 pounds ( View shipping rates and policies ), ASIN: B017RZ8EO4, Item model number: 091922240, Date first listed on Amazon: February 12, 2016, Average Customer Review: 5.0 out of 5 stars 2 customer reviews
Product price: $245.27 - $307.88
Target attributes: Neckline
Answer: attribute: neckline
value: halter
source: product title