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".

Q: What do I have on the schedule on February 4th?

A: user
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Q: I've changed "Staff Meeting" to be Mark.

A: agent
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Q: Decline meeting with new customers and say I will be out of the office all day.

A:
user
****