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: Breedlove Passport OM/Mme Guitar
Product description: Breedlove Passport OM/MMe OM Body,Mahogany top,back,sides,Active Pickup w/chromatic tuner
Product feature: Mahogany Top, Back, Sides, Non Cutaway, Satin Finish, Active pickup with back-lit chromatic tuner, Pre-War Forward X Bracing Pattern
Product brand: Breedlove
Target attributes: Number of Strings
Answer: attribute: number of strings
value: None
source: None