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: Watching Avatar and wondering why I took so long to watch this *collapses in a joyous heap*
This tweet contains emotions: 
joy