<Table> <Tr> <Th_colspan="2"> 2017 Gerry Weber Open </Th> </Tr> <Tr> <Th> Date </Th> <Td> 19--25 June </Td> </Tr> <Tr> <Th> Edition </Th> <Td> 25th </Td> </Tr> <Tr> <Th> </Th> <Td> ATP World Tour 500 </Td> </Tr> <Tr> <Th> Draw </Th> <Td> 32S / 16D </Td> </Tr> <Tr> <Th> Prize money </Th> <Td> € 1,836,660 </Td> </Tr> <Tr> <Th> Surface </Th> <Td> Grass </Td> </Tr> <Tr> <Th> Location </Th> <Td> Halle, Germany </Td> </Tr> <Tr> <Th> Venue </Th> <Td> Gerry Weber Stadion </Td> </Tr> <Tr> <Th_colspan="2"> Champions </Th> </Tr> <Tr> <Th_colspan="2"> Singles </Th> </Tr> <Tr> <Td_colspan="2"> Roger Federer </Td> </Tr> <Tr> <Th_colspan="2"> Doubles </Th> </Tr> <Tr> <Td_colspan="2"> Łukasz Kubot / Marcelo Melo </Td> </Tr> <Tr> <Th_colspan="2"> </Th> </Tr> <Tr> <Td_colspan="2"> <Table> <Tr> <Td> ← 2016 </Td> <Td> Gerry Weber Open </Td> <Td> 2018 → </Td> </Tr> </Table> </Td> </Tr> </Table> <Tr> <Th_colspan="2"> 2017 Gerry Weber Open </Th> </Tr>

Who has won the 2017 gerry weber open tennis tournament
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