Definition: Given a 'poster' sentence and a corresponding 'response' (often, from Facebook or Reddit)classify the sentiment of the given response into four categories: 1) Positive, 2) Negative, 3) Neutral, and 4) Mixed if it contains both positive and negative.
Input: Poster: Getting excited for Comic Con this weekend. Who's coming to our Grimm panel on Saturday? 2:30 Ballroom 20. Yay!  Responser: I wish!!!! Have a great time in San Diego!
