Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.

Example input: I've read this book with much expectation, it was very boring all through out the book
Example output: Negative
Example explanation: Review writer does not like the book because it was boring, therefore it is a negative review.
Q: As a student and teacher of economics, this book has proved to be an invaluable resource! The lesson is simple and direct, yet one that many people fail to apply. This should be required reqding for anyone involved in the development of economic policy (or any other arm of policy making, for that matter). Whether you agree with Hazlitt's conclusions about how the market works or not, you cannot dispute the key lesson of this book. It is entertaining to read, particularly easy for a book about economics. I highly recommend it!
A:
Positive