Task: Classify the mental state of the tweeter based on the tweet, determining if it is 'neutral or no emotion' or characterized by any of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
Tweet: A #smile can mean a thousand words, but it can also hide a thousand #problems. #Fact #TeamFollowBack
This tweet contains emotions: 
joy, optimism, sadness