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: Sending best wishes for a happy #FirstDayOfSchool to the students, teachers, and staff in #Montebello Unified! #MUSD  Responser: https://www.facebook.com/photo.php?fbid=10155929655275632&set=a.235974600631.287698.711170631&type=1
