Task: Evaluate the tweet for emotional cues and classify it as either 'neutral or no emotion' or as one or more of the specified emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that indicate the tweeter's state of mind.
Tweet: @Groupon_UK who do I contact about a shocking experience with Clear Sky Holidays booked through you guys?? #customerservicefail #dreadful
This tweet contains emotions: 
anger, disgust