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: I got a NO RESPONSE again from an #irate customer of #amazon 😞😞\nwhy can't they understand that it's not always amazon fault..\n#carrierfault
This tweet contains emotions: 
anger, disgust, pessimism, sadness