The video, posted on YouTube by the Canadian Olympic and Paralympic teams, features athletes and the two politicians dancing and lip syncing to the song.
On mobile? Click here to watch the Canadian Olympic Team's version of Happy on YouTube
Written and performed by American singer and producer Williams, the song has been a worldwide hit. When first released, the song was accompanied by a music video lasting 24 hours, showing Williams and various others, including celebrities, dancing all over LosAngeles.
It has spawned thousands of cover videos on YouTube.
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