Question: Which French driver, formerly from Team Mugen, replaced Daniil Kvyat as a driver of the Toro Rosso STR12?

Context paragraphs:
Toro Rosso STR12: The Toro Rosso STR12 is a Formula One racing car designed and constructed by Scuderia Toro Rosso to compete during the 2017 Formula One season.  The car made its competitive début at the 2017 Australian Grand Prix and is driven by Daniil Kvyat and Carlos Sainz, Jr. Pierre Gasly replaced Kvyat ahead of the 2017 Malaysian Grand Prix.  The STR12 is powered by engines supplied by Renault after the team used 2015-specification Ferrari power units throughout the season; however, the engines were rebadged and the engine and chassis package run under the name 'Toro Rosso'.

Scuderia Toro Rosso: Scuderia Toro Rosso, commonly known as Toro Rosso or by its abbreviation STR, is an Italian Formula One racing team.  It is one of two F1 teams owned by Austrian beverage company Red Bull, the other being Red Bull Racing.  Toro Rosso functions as a junior team to Red Bull Racing, with the aim of developing the skills of promising drivers for the senior team.  Since 2010, the team has competed entirely independently of their sister team.

Red Bull RB12: The Red Bull RB12 is a Formula One racing car designed by Red Bull Racing to compete in the 2016 Formula One season.  The car was driven by Daniel Ricciardo and Max Verstappen.  Scuderia Toro Rosso driver Verstappen was promoted to Red Bull after swapping places with Daniil Kvyat ahead of the Spanish Grand Prix .  The car is very similar compared to the Red Bull RB11, albeit in a revised livery introduced before the start of the season.  The car used a Renault engine re-badged as a TAG Heuer following the breakdown in the relationship between Red Bull and Renault in .  This was the last Red Bull car with fuel and lubricants from Total — ending their eight-year partnership.

Daniil Kvyat: Daniil Vyacheslavovich Kvyat (Russian: Дании́л Вячесла́вович Квят ; ] , born 26 April 1994) is a Russian auto racing driver.  He was runner-up at the 2012 Eurocup Formula Renault 2.0, and GP3 Series champion in 2013.  He joined Formula One as a Toro Rosso driver in 2014 finishing 15th in the World Championship.  He then moved on to Red Bull Racing to partner Daniel Ricciardo for the 2015 season.  He scored his first Formula One podium finish at the Hungarian Grand Prix on 26 July 2015, finishing second behind Sebastian Vettel.  He returned to Toro Rosso ahead of the 2016 Spanish Grand Prix.

Toro Rosso STR6: The Toro Rosso STR6 is a Formula One racing car developed by Scuderia Toro Rosso for the 2011 Formula One season.  It is the second car that the team has built entirely on their own following the introduction of regulations that banned the use of "customer chassis", a chassis developed by one team and purchased by another (prior to 2010 Toro Rosso used a customer chassis from its "big brother" Red Bull Racing).

Toro Rosso STR8: The Toro Rosso STR8 (initially referred to as the Toro Rosso STR08) is a Formula One racing car designed and built by Scuderia Toro Rosso for use in the 2013 Formula One season.  It was driven by Daniel Ricciardo and Jean-Éric Vergne, both of whom drove for the team in 2012.  This is the last Toro Rosso car for the engine to be named as Ferrari that have powered the team since 2007 despite opted for one-year old engine, before they could used Renault engine for 2014 Formula One season.  This was also the last Toro Rosso car to be used V8 engine, before replaced V6 engine for 2014.

Toro Rosso STR11: The Toro Rosso STR11 is a Formula One racing car designed by Scuderia Toro Rosso to compete in the 2016 Formula One season.  The car was driven by Carlos Sainz, Jr. and Daniil Kvyat, who swapped seats with Max Verstappen, who drove the car in the first four Grands Prix of the season.  It used Ferrari's -specification power unit, the 060.

Toro Rosso STR2: The Toro Rosso STR2 is the car with which the Scuderia Toro Rosso team competed in the Formula One season.  It was unveiled on February 13, 2007 at the Circuit de Catalunya.  The car is, controversially, a variant of the Red Bull RB3 chassis (although powered by a Ferrari instead of a Renault engine).  It was initially driven by Vitantonio Liuzzi and Scott Speed, until Speed was replaced by Sebastian Vettel at the Hungaroring for the remainder of the season.  The car in a modified form was also used to compete in the first four races of the Formula One season.  The modified car was driven by Sébastien Bourdais, four-consecutive-time Champ Car winner, and Vettel.  The STR2 was the first-ever Toro Rosso F1 car to use the mandatory 90-degree Formula One V8 engine configuration but Toro Rosso opted for the 2006-spec Ferrari 056 instead of the 2007-spec because of 1-year old Toro Rosso engine policy and also cost reasons.

Pierre Gasly: Pierre Gasly (born 7 February 1996 in Rouen) is a French formula racing driver, who was the 2014 Formula Renault 3.5 Series runner-up and the 2016 GP2 Series champion.  He drives a Honda-powered car for Team Mugen in the 2017 Super Formula Championship.  He will make his Formula One début at the 2017 Malaysian Grand Prix.

Toro Rosso STR9: The Toro Rosso STR9 is a Formula One racing car designed by Scuderia Toro Rosso to compete in the 2014 Formula One season.  It was driven by Jean-Éric Vergne and 2013 GP3 Series champion Daniil Kvyat, who replaced Daniel Ricciardo after Ricciardo moved to Red Bull Racing.  The STR9 was the first Toro Rosso car to use an engine built by Renault, the Energy F1-2014.

Supporting paragraphs: Toro Rosso STR12 Pierre Gasly
Answer: Pierre Gasly