Detailed Instructions: In this task, you're given a review from Amazon. Your task is to generate a rating for the product on a scale of 1-5 based on the review. The rating means 1: extremely poor, 2: poor, 3: neutral, 4: good, 5: extremely good.
Q: Overall the book was very good. I loved the world and the characters the author created. I felt a few chapters dragged on just a bit, but overall I enjoyed the book very much.
A:
4