Task: Identify the primary emotion conveyed in the tweet and assign it to either 'neutral or no emotion' or one or more of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that best capture the tweeter's mental state.
Tweet: @BorisJohnson unhappy about the cost of leaving the EU ? If only you had published your letter outlining the reasons to stay instead. Idiot.
This tweet contains emotions: 
anger, sadness