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

Input:
Product title: Asian Heirloom Yu Choi (Edible Rape) by Stonysoil Seed Company
Product description: This has become a favorite green of mine. I love it stir fried in my wok with a bit of soy and served with a dash of toasted sesame oil
Product feature: Packet contains 150 plus seeds handpacked with heart and care by Stonysoil Seed Company, Grow as spring or early fall crops ans plants thrive during cooler seasons, Young leaves , inner stalks and flower buds are especially delicous used in light stirfrys, steamed or in soups, Fast growing likes enriched soil or compost, Can be grown in containers ,fertile garden beds ,great for urban spaces as well, Our Gift to You Save 15% off any total order over $20 or 20% off any order over $50 or 25% off any order over$100 Here's how (restrictions apply)
Product price: $7.95
Product brand: Stonysoil Seed Company
Target attributes: Sustainability
Answer: attribute: sustainability
value: None
source: None