Instruction: Extract the value of the target attribute from the given product information and output it along with the corresponding source.

Input:
Product title: Pignose PGG-200 Deluxe Electric Guitar with Built-In Amp (Red)
Product description: PGG-200 mini Electric Guitar with built in amplifier in colors Sunburst or Red.
Product feature: Red, Mini Electric Guitar with built in amplifier in colors Sunburst or Red.
Product price: $62.99
Product brand: Pignose
Target attributes: Number of Strings
Answer: attribute: number of strings
value: None
source: None