Task: Assess the emotional content of the tweet and classify it as either 'neutral or no emotion' or as one or more of the given emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that best represent the tweeter's mental state.
Tweet: Dear everyone at HSSU, stop walking with your phones up so I can smile and wave at you and you can smile and wave back :(
This tweet contains emotions: 
sadness