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: Magic: the Gathering - Sinkhole - Alpha
Product description: Magic: the Gathering is a collectible card game created by Richard Garfield. In Magic, you play the role of a planeswalker who fights other planeswalkers for glory, knowledge, and conquest. Your deck of cards represents all the weapons in your arsenal. It contains the spells you know and the creatures you can summon to fight for you. Card Name : Sinkhole Cost : BB Color : Black Card Type : Sorcery Card Text : Destroy target land.
Product feature: A single individual card from the Magic: the Gathering (MTG) trading and collectible card game (TCG/CCG)., This is of Common rarity., From the Alpha set.
Product brand: Magic: The Gathering
Target attributes: Game
Answer: attribute: game
value: planeswalker
source: product description
attribute: game
value: magic: the gathering
source: product brand
attribute: game
value: magic: the gathering
source: product description
attribute: game
value: planeswalkers
source: product description
attribute: game
value: magic: the gathering
source: product title
attribute: game
value: magic: the gathering
source: product feature