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: You have one event on your calendar. Your Doctor Appointment is on February 1st from 9:00 to 9:30 AM.
Example Output: agent

Example Input: Yeah, looks good thank you.
Example Output: user

Example Input: Oh, I meant Saturday at 9 am.
Example Output:
user