Instruction: First, identify the target attributes from the provided list. Then, scan the product title, description, feature, and brand to extract the values associated with each target attribute. Finally, create a list of dictionaries, each containing the extracted attribute, its corresponding value, and the source where it was found.

Input:
Product title: ValueBull USA Sliced Bison Liver Dog Chews, 5 Pound
Product description: 100% natural bison made in the USA, ValueBull USA Sliced Bison Liver 5 lb is great for big and small dogs alike and can be broken up and used for training. Excellent alternative for dogs with allergies.
Product feature: 100% natural bison, Long-lasting flavor, 100% digestible, Satisfies dogs' natural urge to chew, Made in the USA
Product price: $119.99
Product brand: ValueBull USA
Target attributes: Chew Type
Answer: attribute: chew type
value: None
source: None