You will be given a definition of a task first, then some input of the task.
The input is taken from a negotiation between two participants who take the role of campsite neighbors and negotiate for Food, Water, and Firewood packages, based on their individual preferences and requirements. Given an utterance and recent dialogue context containing past 3 utterances (wherever available), output Yes if the utterance contains the vouch-fair strategy, otherwise output No. vouch-fair is a selfish negotiation strategy. It is used to call out fairness for personal benefit, either when acknowledging a fair deal or when the opponent offers a deal that benefits them. This can be through an explicit call out or can be implied.

Context: 'If you make it two food, we have a deal.' 'I would rather let you have the third water than other food. I don't like fish. ☹️' 'Okay, you can have two firewood and and two food, I'll take the rest.'
Utterance: 'Ok. That seems fair enough to me.'
Output:
Yes