Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Input: Consider Input: Which TV screenwriter created the science fiction shows, Survivors and Blake's Seven?

Output: blake's 7


Input: Consider Input: The rivers Axe, Brue, Cary, Parrett, eta, are in which English county?

Output: castle cary


Input: Consider Input: How were Dr Stantz, Dr Spengler and Dr Venkman better known in the 1980's?


Output: peter venkman