Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

Example Input: paranthropus is an extinct genus of robust australopithecines.
Example Output: paranthropus

Example Input: leni robredo (born april 23, 1965) is a filipina lawyer and politician.
Example Output: leni robredo

Example Input: forseti is a god of justice and reconciliation in norse mythology.
Example Output:
forseti