<Table> <Tr> <Th_colspan="2"> Men's 400 metres at the Games of the XXXI Olympiad </Th> </Tr> <Tr> <Td_colspan="2"> Interior view of the Estádio Olímpico João Havelange, where the Men's 400m took place . </Td> </Tr> <Tr> <Th> Venue </Th> <Td> Olympic Stadium </Td> </Tr> <Tr> <Th> Dates </Th> <Td> 12 August 2016 (Heats) 13 August 2016 (semi-final) 14 August 2016 (final) </Td> </Tr> <Tr> <Th> Competitors </Th> <Td> 53 from 33 nations </Td> </Tr> <Tr> <Th> Winning time </Th> <Td> 43.03 WR </Td> </Tr> <Tr> <Th_colspan="2"> Medalists </Th> </Tr> <Tr> <Td_colspan="2"> <Table> <Tr> <Th> 01! </Th> <Td> </Td> <Td> Wayde van Niekerk </Td> <Td> South Africa </Td> </Tr> <Tr> <Th> 02! </Th> <Td> </Td> <Td> Kirani James </Td> <Td> Grenada </Td> </Tr> <Tr> <Th> 03! </Th> <Td> </Td> <Td> LaShawn Merritt </Td> <Td> United States </Td> </Tr> </Table> </Td> </Tr> <Tr> <Td_colspan="2"> ← 2012 2020 → </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Men's 400 metres at the Games of the XXXI Olympiad </Th> </Tr>

Who won the gold medal in 400m sprint in 2016 summer olympics
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