Instruction: Using the product's title, description, features, price, and brand, identify and retrieve the values associated with a specified set of target attributes. Output the extracted values along with their respective sources (e.g., title or feature) indicating where each value was found.

Input:
Product title: Serengeti San Remo Sunglasses, Shiny Hematite Frame, Drivers Lens
Product description: Demanding the best in function and style the San Remo utilize classic designs with a modern twist. Titanium and acetate frames allow for maximum adjustability and unmatched durability. The ultra light lens technology provides superior optical acuity. All Serengeti lenses offer the latest in photochromic technology, which constantly lightens and darkens throughout the day to ensure you see every detail.
Product feature: Photochromic lenses constantly adjust to changing light conditions, Spectral Control diminishes haze and distracting glare, enhances contrast and sharpens your vision, 100% UVA/UVB Protectant, Ultra-Light Glass Lenses, Titanium Frame/Acetate Temples and Spring Hinges
Product brand: Serengeti
Target attributes: Lens Color
Answer: attribute: lens color
value: None
source: None