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".

Example Input: I've changed "Meeting with Sarah and Damon Straeter" to be on Wednesday the 18th.
Example Output: agent

Example Input: Add watch QVC Thursday night from 5:15p to 3am
Example Output: user

Example Input: Where is my flight tomorrow at 9 am?
Example Output:
user