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: Just had #efficient #great #smiling service @AppleBelgique store. Impressive team of geniuses ready to redefine what customer service is!
This tweet contains emotions: 
joy