In this task, you are given an utterance, which is a part of a conversation between a user and an agent. Your job is to detect the speaker. The user usually commands the agent to schedule events, retrieve event information, and check the schedule. While the agent's response is an answer to the user's questions or follow-up questions on the user's command. Answer with "User" or "Agent".

[EX Q]: No, I didn't find any events this weekend.
[EX A]: agent

[EX Q]: No, I didn't find any events between December 1st and February 29, 2020.
[EX A]: agent

[EX Q]: accept the invite to Vacation in Sweden
[EX A]:
user