Question: Which German Formula One racing driver shared the lead in the with Lewis Hamilton in the lead in 2017 Formula One Driver's Championship?

full_context: Document 1: 2017 Australian Grand Prix: The 2017 Australian Grand Prix (formally known as the 2017 Formula 1 Rolex Australian Grand Prix) was a Formula One motor race that took place on 26 March 2017 in Melbourne. The race was contested over fifty-seven laps of the Melbourne Grand Prix Circuit and was the first round of the 2017 FIA Formula One World Championship. The race marked the eighty-first race in the combined history of the Australian Grand Prix – which dates back to the 100 Miles Road Race of 1928 – and the twenty-second time the event was held at the Melbourne Grand Prix Circuit. The reigning World Champion Nico Rosberg was the winner of the 2016 race, but he did not defend his win as he retired from the sport after the 2016 season.
Document 2: 2013 Indian Grand Prix: The 2013 Indian Grand Prix (formally the 2013 Formula 1 Airtel Indian Grand Prix) was a Formula One motor race held on 27 October 2013 at the Buddh International Circuit, Greater Noida, Uttar Pradesh, India. It was the sixteenth round of the 2013 Formula One season, and the third Indian Grand Prix. The race, contested over 60 laps, was won by Sebastian Vettel, driving a Red Bull, from a pole position start. Nico Rosberg finished second in a Mercedes, with Romain Grosjean third for the Lotus team. Vettel's win confirmed him as 2013 Drivers' Champion, as Fernando Alonso could not pass Vettel's points total with only three races remaining. Red Bull also clinched their fourth consecutive Constructors' Championship.
Document 3: Lewis Hamilton: Lewis Carl Davidson Hamilton, MBE, (born 7 January 1985) is a British racing driver who races in Formula One for the Mercedes AMG Petronas team. A three-time Formula One World Champion, he is often considered the best driver of his generation and widely regarded as one of the greatest Formula One drivers in the history of the sport. He won his first World Championship title with McLaren in 2008 before moving to Mercedes, where he won back-to-back titles in 2014 and 2015. Hamilton has more race victories than any other British driver in the history of Formula One ( ), and holds records for the all-time most career points ( ), the most wins at different circuits (24), the all-time most pole positions ( ), as well as achieving the joint-most podium finishes in a season (17). Hamilton is also the only driver to have won at least one Grand Prix in every season he has competed in.
Document 4: Sebastian Vettel: Sebastian Vettel (] ; born 3 July 1987) is a German racing driver currently driving in Formula One for Scuderia Ferrari. He is a four-time Formula One World Champion, having won the championship in , , and with Red Bull Racing, therefore being among the most successful F1 drivers of all time, as he is one of only four drivers to have won four or more drivers' titles. He is regarded by fellow and former drivers as one of the greatest Formula One drivers in the history of the sport. Vettel signed a three-year contract with Ferrari upon his arrival, a contract later extended until the end of 2020.
Document 5: 2010 FIA Formula One World Championship: The 2010 FIA Formula One World Championship was the 64th season of FIA Formula One motor racing. Red Bull Racing won its maiden Constructors' Championship with a one-two finish in Brazil, while Red Bull Racing's Sebastian Vettel won the Drivers' Championship after winning the final race of the season. In doing so, Vettel became the youngest World Drivers' Champion in the sport's sixty-year history. Vettel's victory in the championship came after a dramatic season finale at Abu Dhabi where three other drivers could also have won the championship – Vettel's Red Bull Racing teammate Mark Webber, Ferrari's Fernando Alonso and McLaren's Lewis Hamilton.
Document 6: 2017 Bahrain Grand Prix: The 2017 Bahrain Grand Prix (formally known as the 2017 Formula 1 Gulf Air Bahrain Grand Prix) was a Formula One motor race that took place on 16 April 2017 at the Bahrain International Circuit in Sakhir, Bahrain. The race was the third round of the 2017 season and marked the thirteenth time that the Bahrain Grand Prix has been run as a round of the Formula One World Championship. The winner of the previous Bahrain Grand Prix, Nico Rosberg, did not compete as he had retired after the 2016 season. Before the race, Sebastian Vettel and Lewis Hamilton shared the lead in the Drivers' Championship. Mercedes led the Constructors' Championship by one point over Ferrari.
Document 7: Max Verstappen: Max Emilian Verstappen (] ; born 30 September 1997) is a Belgian-Dutch racing driver who competes under the Dutch flag in Formula One with Red Bull Racing. Aged , he became the youngest driver to compete in Formula 1 at the 2015 Australian Grand Prix for Scuderia Toro Rosso. He is also the youngest driver to lead a lap during a Formula One Grand Prix, youngest driver to set the fastest lap during a Formula One Grand Prix, youngest driver to score points, youngest driver to secure a podium and youngest Formula One Grand Prix winner in history.
Document 8: 2012 Bahrain Grand Prix: The 2012 Bahrain Grand Prix (formally known as the 2012 Formula 1 Gulf Air Bahrain Grand Prix) was a Formula One motor race held on 22 April 2012 at the Bahrain International Circuit in Sakhir, Bahrain. It was the first time Formula One returned to Bahrain after the 2011 race was cancelled due to ongoing anti-government protests. The race, the eighth running of the Bahrain Grand Prix, was contested over 57 laps and was the fourth round of the 2012 Formula One season.
Document 9: 2017 Bahrain FIA Formula 2 round: The 2017 Bahrain FIA Formula 2 round were a pair of motor races held on 15 and 16 April 2017 at the Bahrain International Circuit in Sakhir, Bahrain as part of the FIA Formula 2 Championship. It was the first round of the 2017 FIA Formula 2 Championship and was run in support of the 2017 Bahrain Grand Prix.
Document 10: Michael Schumacher: Michael Schumacher (] ; born 3 January 1969) is a retired German racing driver who raced in Formula One for Benetton and Ferrari, where he spent the majority of his career, as well as for Mercedes upon his brief return to the sport. Widely regarded as one of the greatest Formula One drivers, and regarded by some as the greatest of all time, Schumacher is the only driver in history to win seven Formula One World Championships, five of which he won consecutively. The most successful driver in the history of the sport, Schumacher holds the records for the most World Championship titles (7), the most Grand Prix wins (91), the most fastest laps (77) and the most races won in a single season (13), and according to the official Formula One website, Schumacher is "statistically the greatest driver the sport has ever seen".
Document 11: 2015 Bahrain Grand Prix: The 2015 Bahrain Grand Prix (formally known as the 2015 Formula 1 Gulf Air Bahrain Grand Prix) was a Formula One motor race that was held on 19 April 2015 at the Bahrain International Circuit in Sakhir, Bahrain. The race was the fourth round of the 2015 season and marked the eleventh time that the Bahrain Grand Prix has been run as a round of the Formula One World Championship.
Document 12: 2014 Bahrain Grand Prix: The 2014 Bahrain Grand Prix (formally the 2014 Formula 1 Gulf Air Bahrain Grand Prix) was a Formula One motor race held on 6 April at the Bahrain International Circuit in Sakhir, Bahrain. It was the third round of the 2014 Formula One season, the 900th Formula One World Championship event, and the eleventh running of the race. The 57-lap race was won by Mercedes driver Lewis Hamilton who started from second position. His teammate Nico Rosberg finished second and Force India driver Sergio Pérez came in third. It was Hamilton's second victory of the season, his first in Bahrain, and the 24th of his Formula One career.
Document 13: Niki Lauda: Andreas Nikolaus "Niki" Lauda (born 22 February 1949) is an Austrian former Formula One driver and a three-time F1 World Drivers' Champion, winning in 1975, 1977 and 1984. He is currently the only driver to have been champion for both Ferrari and McLaren, the sport's two most successful constructors. More recently an aviation entrepreneur, he has founded and run two airlines (Lauda Air and Niki). He is also Bombardier Business Aircraft brand ambassador. He was also a consultant for Scuderia Ferrari and team manager of the Jaguar Formula One racing team for two years. He is currently working as a pundit for German TV during Grand Prix weekends and acts as non-executive chairman of the Mercedes AMG Petronas F1 Team. Lauda owns 10% of the team.
Document 14: Formula One drivers from Germany: There have been 52 Formula One drivers from Germany including three world champions, one of whom is currently racing in the sport. Michael Schumacher holds many records in F1 including the most world championship titles and the most consecutive titles. In 2008 Sebastian Vettel became the youngest ever driver to win a race (which was later broken) and, in 2010, became the youngest world championship winner. In 2016, Nico Rosberg became the third driver from Germany to win the F1 drivers' championship. There are currently three German race drivers in Formula One.
Document 15: Red Bull RB9: The Red Bull RB9 is a racing car designed by Formula One racing team Infiniti Red Bull Racing. The car was driven throughout the 2013 Formula One season by (then) three-time World Drivers' Champion Sebastian Vettel and team-mate Mark Webber. Sebastian Vettel, in keeping with his tradition of naming his cars, named his RB9 "Hungry Heidi," after German model Heidi Klum. Vettel would ultimately claim the Drivers' Championship title, for the fourth consecutive season, at the Indian Grand Prix , after ten wins during the season. Vettel and Webber also brought the car to the last win and world titles for a V8 and a naturally aspirated engine powered F1 car, marking the end of the V8 and the naturally aspirated engine era of Formula One which began in 1989 when turbocharged engines were banned at that time.
ground_truth: Sebastian Vettel