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: It's now September and we're still battling a situation that was said to be handled March of this year. @ATT this is unacceptable #unhappy
This tweet contains emotions: 
anger, sadness