TASK DEFINITION: In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.
PROBLEM: Who was the 20th prime minister of canada?

SOLUTION: Jean Chretien

PROBLEM: When was the first battle of panipath fought?

SOLUTION: 21 April 1526

PROBLEM: When were the first ancient olympic games held?

SOLUTION:
(mid-summer) 765 BC