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: Had such an amazing time at The White House! Thank you Usta for letting me be apart of this amazing experience #GimmieFive  Responser: For a full seven seconds I was wondering "Who is this 'Usta' person you speak of?"
