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: The pool party isn't starting until 1 pm now.
Example Output: user

Example Input: I need to move the staff meeting next week back to the 28th at 10 am
Example Output: user

Example Input: I've deleted your event matching "coffee".
Example Output:
agent