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

Input: Consider Input: The Byzantine Empire is the term used since the 19th century to describe the Roman Empire of the Middle Ages, centred on its capital, where?

Output: byzantine empire

Input: Consider Input: Which horse won the 2008 Grand National?

Output: 2008 grand national

Input: Consider Input: What is the pen name of American author Daniel Handler who wrote the children's book 'A Series of Unfortunate Events'?
Output: daniel handler