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 Dickens novel is subtitled The Parish Boy's Progress?

Output: charles dickens


Input: Consider Input: Who succeeded Jon Pertwee as Doctor Who?

Output: doctor who


Input: Consider Input: Who wrote the 1939 book The Big Sleep?


Output: the big sleep