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 "Summer at the Park" to be.
Example Output: agent

Example Input: add dinner with Barack Obama for wednesday at 8pm
Example Output: user

Example Input: Actually I meant the day after tomorrow.
Example Output:
user