<Table> 2017 National Football League season <Tr> <Th_colspan="2"> Regular season </Th> </Tr> <Tr> <Th> Duration </Th> <Td> September 7, 2017 (2017 - 09 - 07)--December 31, 2017 (2017 - 12 - 31) </Td> </Tr> <Tr> <Th_colspan="2"> Playoffs </Th> </Tr> <Tr> <Th> Start date </Th> <Td> January 6, 2018 </Td> </Tr> <Tr> <Th_colspan="2"> Super Bowl LII </Th> </Tr> <Tr> <Th> Date </Th> <Td> February 4, 2018 </Td> </Tr> <Tr> <Th> Site </Th> <Td> U.S. Bank Stadium, Minneapolis, Minnesota </Td> </Tr> <Tr> <Th_colspan="2"> </Th> </Tr> <Tr> <Th_colspan="2"> Pro Bowl </Th> </Tr> <Tr> <Th> Date </Th> <Td> January 28, 2018 </Td> </Tr> <Tr> <Th> Site </Th> <Td> Camping World Stadium, Orlando, Florida </Td> </Tr> <Tr> <Th_colspan="2"> </Th> </Tr> <Tr> <Td_colspan="2"> <Ul> <Li> ← 2016 </Li> <Li> NFL seasons </Li> </Ul> </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Regular season </Th> </Tr>

How many weeks are in the nfl season 2017
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