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: No, move to the 28th
Example Output: user

Example Input: Delete my meeting on Saturday
Example Output: user

Example Input: Yes, schedule the Monday appt at 130 and add Susan, Betsy and Michelle to the group.
Example Output:
user