Question: Who hosted Saturday Night Live during the premier episode of the season in which Luke Null joined the cast?

Context paragraphs:
A Night at the Roxbury: A Night at the Roxbury is a 1998 American comedy film based on a recurring skit on television's long-running "Saturday Night Live" called "The Roxbury Guys".  "Saturday Night Live" regulars Will Ferrell, Chris Kattan, Molly Shannon, Mark McKinney and Colin Quinn star.  This film expands on the original Saturday Night Live sketches where the Roxbury Guys were joined by that week's host, and bobbed their heads to Haddaway's hit song "What Is Love" while being comically rejected by women at various clubs.

Saturday Night Live from Milano: Saturday Night Live from Milano, Also known as Saturday Night Live Italy, was the Italian localisation of the popular US-comedy television series "Saturday Night Live", shown on Mediaset television channel Italia 1 from 2006.

Saturday Night Live: Saturday Night Live (abbreviated as SNL) is an American late-night live television sketch comedy and variety show created by Lorne Michaels and developed by Dick Ebersol.  The show premiered on NBC on October 11, 1975, under the original title NBC's Saturday Night.  The show's comedy sketches, which parody contemporary culture and politics, are performed by a large and varying cast of repertory and newer cast members.  Each episode is hosted by a celebrity guest (who usually delivers an opening monologue and performs in sketches with the cast) and features performances by a musical guest.  An episode normally begins with a cold open sketch that ends with someone breaking character and proclaiming, "Live from New York, it's Saturday Night! ", properly beginning the show.

Luke Null: Luke Null (born July 7, 1990 in Cincinnati, Ohio) is an American actor, comedian, and singer, who currently works as a cast member on "Saturday Night Live", having joined the show at the start of its forty-third season.  Prior to joining the show, Null was known for performing at the iO Theater in Chicago specializing in musical comedy.  Luke Null is now the second "SNL" cast member born in the 1990s after Pete Davidson (though Null is older than Davidson by three years).

SNL Studios: SNL Studios is a production company, founded in July 1997 as a joint venture between "Saturday Night Live" executive producer Lorne Michaels and NBC Studios (now Universal Television, the production arm of NBCUniversal).  While this venture also initially included Paramount Pictures, it was dissolved following NBC's merger with Universal Studios.  On the television side, SNL Studios produces "Saturday Night Live" in association with Broadway Video.  Film productions, typically offshoots of Saturday Night Live' sketches, include, among others, "A Night at the Roxbury" and "Superstar".

Jay Pharoah: Jared Antonio Farrow (born 14 October, 1987) better known by his stage name Jay Pharoah, is an American actor, stand-up comedian, impressionist, rapper, and voice actor.  He joined the cast of NBC's "Saturday Night Live" in 2010, for its thirty-sixth season.  In 2015, he was ranked the 55th greatest "Saturday Night Live" cast member by "Rolling Stone" magazine.

List of Saturday Night Live guests: "Saturday Night Live" (abbreviated as SNL) is a late-night sketch comedy and variety show created by Lorne Michaels.  It premiered on NBC, a terrestrial television network, on October 11, 1975 under the title "NBC's Saturday Night".  The show often satirizes contemporary American popular culture and politics.  "Saturday Night Live" features a two-tiered cast: the repertory members, also known as the "Not Ready for Prime-Time Players", and newer cast members, known as "Featured Players."

Saturday Night Live (season 43): The forty-third season of the NBC comedy series "Saturday Night Live" premiered on September 30, 2017 with host Ryan Gosling and musical guest Jay-Z during the 2017–2018 television season.  Like the final four episodes of season 42, season 43 will be broadcast live in all four time zones within the contiguous United States.

List of Saturday Night Live episodes: <section begin=head />"Saturday Night Live" ("SNL") is a late-night sketch comedy and variety show created by Lorne Michaels.  It premiered on NBC, a terrestrial television network, on October 11, 1975 under the title "NBC's Saturday Night".  The show often satirizes contemporary American popular culture and politics.  "Saturday Night Live" features a two-tiered cast: the repertory members, also known as the "Not Ready for Prime-Time Players," and newer cast members, known as "Featured Players."  Each week, the show features a host, often a well-known celebrity, who delivers an opening monologue and performs in sketches with the cast.  A musical guest is also invited to perform several sets (usually two, and occasionally more).  Every so often a host or musical guest will fill both roles, such as was the case with Britney Spears in 2000 and 2002, Jennifer Lopez in 2001 and 2010, Justin Timberlake in 2003, 2006 and 2013, Taylor Swift in 2009, Bruno Mars in 2012, Lady Gaga in 2013, Miley Cyrus in 2013 and 2015, Drake in 2014 and 2016, Blake Shelton in 2015, and Ariana Grande in 2016.  With the exception of Season 7 and several other rare cases, the show has begun with a cold open that ends with someone breaking character and proclaiming "Live from New York, it's Saturday Night! "

Wayne's World: "Wayne's World" was originally a recurring sketch from the NBC television series "Saturday Night Live".  It evolved from a segment titled "Wayne's Power Minute" (1987) on the CBC Television series "It's Only Rock & Roll", as the main character first appeared in that show.  The "Saturday Night Live" sketch spawned two films, and several catchphrases which have since entered the pop-culture lexicon.  The sketch centered on a local public-access television program in Aurora, Illinois, hosted by Wayne Campbell (Mike Myers, the same actor from "Wayne's Power Minute"), an enthusiastic and sardonic long-haired metalhead, and his timid and sometimes high-strung, yet equally metal-loving sidekick and best friend, Garth Algar (Dana Carvey).  Wayne lives with his parents and broadcasts his show "live" from the basement of their house every Friday evening at 10:30.  The first "Wayne's World" sketch appeared in the 13th "Saturday Night Live" episode of 1988/1989.

Supporting paragraphs: Luke Null Saturday Night Live (season 43)
Answer: Ryan Gosling