Question: Who is the first Irish professional mixed martial artist to hold two UFC championship titles in two different divisions?

full_context: Document 1: José Aldo: José Aldo da Silva Oliveira Junior (] ; born September 9, 1986) is a Brazilian mixed martial artist in the Ultimate Fighting Championship. He was the fourth and final WEC Featherweight Champion and thus, became the first UFC Featherweight Champion during the UFC/WEC merger. He is a former two-time UFC Featherweight Champion. He was named Sherdog's 2009 Fighter of the Year. He is currently #12 in official UFC pound-for-pound rankings, having been ranked as high as #1 in 2015, and ranked the #2 featherweight in the world and #7 pound-for-pound by Sherdog. In the decade from November 2005 through December 2015, Aldo was undefeated in 18 fights. In Sherdog's April 2017 Pound-For-Pound ranking, Aldo was called "the greatest featherweight in mixed martial arts history."
Document 2: UFC Fight Night: McGregor vs. Brandao: UFC Fight Night: McGregor vs. Brandao (also known as UFC Fight Night 46) was a mixed martial arts event held on July 19, 2014, at The O in Dublin, Ireland.
Document 3: Frank Shamrock: Frank Shamrock (born Frank Alisio Juarez, III; December 8, 1972) is an American former mixed martial artist. Shamrock was the first to hold the UFC Middleweight Championship (later renamed the UFC Light Heavyweight Championship) and retired as the four-time defending undefeated champion. Shamrock was the No. 1 ranked pound for pound UFC fighter in the world during his reign as the UFC Middleweight Champion. Shamrock has won numerous titles in other martial arts organizations, including the interim King of Pancrase title, the WEC Light Heavyweight Championship and the Strikeforce Middleweight Championship.
Document 4: Xtreme Couture Mixed Martial Arts: Xtreme Couture Mixed Martial Arts is an American mixed martial arts training organization headed by former UFC Champion and former co-founder of Team Quest, Randy Couture. Xtreme Couture was founded with the flagship gym in Las Vegas. Since then, the franchise has spread to other cities in the United States and Canada. Xtreme Couture Las Vegas is one of the largest gyms (over 24000 sqft ), most recognized brands and MMA gyms in the world where many past and current top MMA fighters train.
Document 5: Michael Chiesa: Michael Keith Chiesa ( ; born December 7, 1987) is an American mixed martial artist. A professional MMA competitor since 2008, Chiesa was the winner of FX's inaugural . He currently fights for the UFC in the lightweight division where he is the #9 contender in official UFC rankings.
Document 6: Mark Coleman: Mark Daniel Coleman (born December 20, 1964) is a retired American mixed martial artist, professional wrestler, former NCAA collegiate wrestler and former Olympic amateur wrestler. Known as The Hammer, he was the UFC 10 and UFC 11 tournament champion, the first UFC Heavyweight Champion, and the Pride Fighting Championships 2000 Open Weight Grand Prix champion. At UFC 82 Coleman was inducted into the UFC Hall of Fame. At the age of retirement he was taking 150,000 USD salary per year.
Document 7: Conor McGregor: Conor Anthony McGregor (Irish: "Conchúr Antóin Mac Gréagóir" ; born 14 July 1988) is an Irish professional mixed martial artist and professional boxer who is currently signed to the Ultimate Fighting Championship (UFC). He is the reigning UFC Lightweight Champion, and former UFC Featherweight Champion. During his mixed martial arts (MMA) career, McGregor has competed as a featherweight, lightweight, and welterweight. As of 2017, McGregor is ranked 2nd on UFC's pound for pound rankings.
Document 8: Randy Couture vs. Chuck Liddell: Randy "The Natural" Couture vs. Chuck "The Iceman" Liddell is a mixed martial arts trilogy. All three fights took place under Ultimate Fighting Championship in the United States. All three fights have ended in knockout and have been for the UFC Light Heavyweight Championship.
Document 9: B.J. Penn: Jay Dee "B.J." Penn (born December 13, 1978) is an American professional mixed martial artist and Brazilian Jiu-Jitsu practitioner. Penn debuted and competed in the Ultimate Fighting Championship (UFC), and later in K-1. Prior to fighting for the UFC, he became the first American Gold medalist of the World Jiu-Jitsu Championship. In mixed martial arts, Penn has competed in the Featherweight, Lightweight, Welterweight, and Middleweight divisions. As a former UFC Lightweight Champion and UFC Welterweight Champion, he is one of only three fighters in UFC history to win titles in multiple weight classes. Penn was also a Co-champion in the UFC 41 Lightweight Tournament, due to an eventual draw opposite Caol Uno in the tournament finale. Through his tenures as champion, Penn unofficially unified the UFC Lightweight Championship (against Sean Sherk) and broke the all-time lightweight title defense record. Penn was inducted into the UFC Hall of Fame, as the inaugural inductee in the Modern-Era Wing by career-long rival Matt Hughes, during "International Fight Week" in July 2015.
Document 10: Dan Henderson: Daniel Jeffery Henderson (born August 24, 1970) is an American former mixed martial artist and Olympic wrestler, who last competed as a middleweight in the Ultimate Fighting Championship. He was the last Strikeforce Light Heavyweight Champion and was the last Welterweight (80 kg ) and Middleweight (95 kg ) champion of Pride Fighting Championships. Additionally, Henderson was the Brazil Open '97 Tournament Champion, the UFC 17 Middleweight Tournament Champion, the Rings: King of Kings 1999 Tournament Champion and the Pride Weltwerweight Grand Prix Tournament Champion. During his career, Henderson also challenged for the UFC Middleweight Championship (2x), the UFC Light Heavyweight Championship and the Strikeforce Middleweight Championship. He was the first mixed martial artist to concurrently hold two titles in two different weight classes in a major MMA promotion. At the time of his retirement after UFC 204, he was the oldest fighter on the UFC roster. Known to be one of the greatest mixed martial artists of all time having defeated a total of seventeen MMA world champions across four major MMA promotions (UFC, PRIDE FC, Strikeforce, and RINGS).
Document 11: Colby Covington: Colby Covington (born February 22, 1988) is an American mixed martial artist who competes in the welterweight division of the Ultimate Fighting Championship. He is currently ranked #8 in the official UFC welterweight rankings.
Document 12: Donald Cerrone: Donald Anthony Cerrone ( ; born March 29, 1983) is an American professional mixed martial artist and former professional kickboxer currently competing in the UFC's Lightweight and Welterweight divisions. He is ranked #6 in the official UFC Welterweight rankings tied with fellow Welterweight contender Neil Magny. A professional competitor since 2006, Cerrone has also formerly competed for the WEC. Cerrone currently holds the record for most post-fight bonuses (Fight/Performance of the Night, Knockout/Submissions of the Night) in UFC/WEC history with 18. He is also known as the "busiest" fighter in the UFC, due to consistently having at least four fights per year since 2013.
Document 13: Anthony Pettis: Anthony Paul Pettis (born January 27, 1987) is an American mixed martial artist currently competing as a Lightweight in the Ultimate Fighting Championship (UFC), where he is the former UFC Lightweight Champion. Pettis was also the final WEC Lightweight Champion prior to the promotion being merged into the UFC. At one point, he was ranked as a top-ten pound for pound fighter. He is currently ranked #13 in the official UFC lightweight rankings.
Document 14: Randy Couture: Randall "Randy" Duane Couture ( ; born June 22, 1963) is an American actor, retired United States Army Sergeant, retired mixed martial artist and former collegiate and Greco-Roman wrestler. During his tenures in the Ultimate Fighting Championship (UFC), Couture became a three-time UFC Heavyweight Champion, two-time UFC Light Heavyweight Champion, an interim UFC Light Heavyweight Champion and the UFC 13 Heavyweight Tournament Winner. Couture is the first of only three fighters to hold two UFC championship titles in two different divisions (along with B.J. Penn and Conor McGregor).
Document 15: Chuck Liddell: Charles David "Chuck" Liddell (born December 17, 1969) is an American retired mixed martial artist and former UFC Light Heavyweight Champion. He has an extensive striking background in American Kenpo, Koei-Kan Karate, and kickboxing, as well as a grappling background in collegiate wrestling and Brazilian jiu-jitsu. He had 23 fights in the UFC; along with Randy Couture, he is widely credited for bringing MMA into the mainstream of American sports and entertainment. On July 10, 2009, he was inducted into the UFC Hall of Fame.
ground_truth: Conor McGregor