In this task, You are given an open-domain question that can be answered based on factual information. Your task is to provide \*short\* answer (in a few words only) for the given question. The short answer can be one or more entities or it can also be boolean \*yes\* or \*no\*.
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Question: who played in the men's semi final in wimbledon in 2015

Answer: Novak Djokovic


Question: when did angel leave buffy the vampire slayer

Answer: 1999


Question: when do you have a scrum in rugby union

Answer:
after a minor infringement