Instruct: Classify a review into positive or negative sentiment.
Query: Very tough and unordered reading

It is a pity but I have to write I am not satisfied with the book. It is kind of a book which does not concetrate on the main purpose of a reading - "to learn something". Of course I understand - it is programmer's reference but even so there is a lot of introductory parts which could be done much better.There are parts that are very very talkative and give nowadays "vain" information and on the other hand there are parts which should be absolutely more narrative. The book reminds me a kind of "scientific" or "academic" book. From this point of view it is quite good. It is for people who have time to read it in their labs. It is the book for a long time. You absolutely learn a lot of useful topics but you have to find your own way of reading.