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: Logitech Wireless Mouse M320, Black
Product description: Enjoyfort for your right hand through curved grips made of soft rubber. Go longer between battery changes thanks to our energy efficient engineering. Plus, m320 automatically puts itself to sleep when youre not using it. Get ultra precision and responsiveness with logitech advanced optical tracking. Plug it once and forget it. Nano receiver gives you a convenient and reliable wireless connectivity.
Product feature: Right-handed contoured design: Curved soft rubber side grips for extra comfort, 2 year battery life: Go longer between battery changes (Battery life may vary based on user and computing conditions), Logitech Advanced Optical Tracking: Enjoy ultra-precise and responsive cursor control, Plug-and-forget Nano receiver: Reliable wireless connection with a small receiver that can stay in your computer's USB port, Wide compatibility: Works with Windows 8/7/Vista/XP, Mac OS X 10.5 or later, Chrome and Linux Kernel 2.6 operating systems, Comfortable contoured shape., Soft rubber grip., Two-year battery life*., Plug-and-forget Nano wireless receiver., Wide scroll wheel., Advanced Optical Tracking., Windows 8, Windows 7, Windows Vista or Windows XP, Mac OS X 10.5 or later, Chrome OS, Linux kernel 2.6+, Internet connection, USB port
Product price: $65.00
Product brand: Logitech
Target attributes: Number of Buttons
Answer: attribute: number of buttons
value: None
source: None