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: And on the 17th?
Example Output: user

Example Input: I need to cancel it.
Example Output: user

Example Input: Tomorrow is Wednesday.
Example Output:
agent