Teacher: In this task, you are given a dialogue between a user and an assistant, where users and assistants converse about geographic topics like geopolitical entities and locations. The task here is to find if the dialogue is by the user or assistant. Classify your answers into user and assistant.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Ok, the national drink of Scotland is whisky.
Solution: assistant
Reason: It is pretty straightforward. It is knowledge sharing, and the assistant explains the question asked by the user.

Now, solve this instance: Seleucus was the only Greek-Babylonian astronomer known to support a heliocentric model of planetary motion.
Student:
assistant