Question: Who created the animated television series that has "The Death of Eric Cartman" as the sixth episode? 

Context paragraphs:
T.M.I. (South Park): "T.M.I." is the fourth episode of the fifteenth season of the American animated television series "South Park", and the 213th episode of the series overall.  "T.M.I." premiered in the United States on Comedy Central on May 18, 2011.  The episode centers on Eric Cartman being sent to an anger management class after he protests what he mistakenly believes to be the school's publicizing the male students' penis sizes.  "T.M.I." was written and directed by series co-creator Trey Parker, and was rated TV-MA-L in the United States.

201 (South Park): "201" is the sixth episode of the fourteenth season of "South Park", and the 201st overall episode of the series.  It originally aired on Comedy Central in the United States on April 21, 2010.  The episode continued multiple storylines from the previous episode, "200", in which a group of angry celebrities demand South Park produce the Muslim prophet Muhammad.  In "201", a superhero-like group of religious figures team up to save South Park from the celebrities and their monster Mecha-Streisand, while Eric Cartman learns the true identity of his father.

Cartman Gets an Anal Probe: "Cartman Gets an Anal Probe" is the first episode of the American animated television series "South Park".  It first aired on Comedy Central in the United States on August 13, 1997.  The episode introduces child protagonists Eric Cartman, Kyle Broflovski, Stan Marsh and Kenny McCormick, who attempt to rescue Kyle's younger brother Ike from being abducted by aliens.

Cartman's Mom Is a Dirty Slut: "Cartman's Mom Is a Dirty Slut" is the first season finale of the American animated television series "South Park".  It originally aired on Comedy Central in the United States on February 25, 1998.  The episode is the highest viewed episode in the entire "South Park" series, with 6.4 million views.  It is part one of a two-episode story arc, which concluded with "Cartman's Mom Is Still a Dirty Slut".  The episode follows Eric Cartman, one of the show's child protagonists, becoming curious about the identity of his father.  He discovers that his father is most likely a man his mother had sexual intercourse with during an annual party called "The Drunken Barn Dance".  Meanwhile, his friends Stan, Kyle and Kenny participate on "America's Stupidest Home Videos", after filming Cartman playing in his yard with plush toys.

Dances with Smurfs: "Dances with Smurfs" is the thirteenth episode of the thirteenth season of the American animated television series "South Park".  The 194th overall episode of the series, it originally aired on Comedy Central in the United States on November 11, 2009.  In the episode, Eric Cartman becomes the reader of the elementary school announcements, and starts making politically charged accusations against student body president Wendy Testaburger The episode was written and directed by series co-creator Trey Parker, and was rated TV-MA L in the United States and M (as) in Australia.

Cartman's Incredible Gift: "Cartman's Incredible Gift" is episode 124 of the Comedy Central series "South Park".  It originally aired December 8, 2004 as part of the series' eighth season.  In the episode, local police become convinced that Eric Cartman has psychic abilities, which Cartman exploits for personal gain, much to the ire of Kyle Broflovski, other psychic detectives, and the true serial killer behind a series of murders that Cartman falsely attributes to others.

Eric Cartman: Eric Theodore Cartman, often referred to as just Cartman, is a main character in the animated television series "South Park", created by Matt Stone and Trey Parker, and voiced by Trey Parker.  Cartman, generally referred to by his surname, is one of four central characters in "South Park", along with his friends Stan Marsh, Kyle Broflovski, and Kenny McCormick.  Cartman first appeared, originally named Kenny, in prototypical form in a 1992 animated short "Jesus vs. Frosty", and a 1995 animated short "Jesus vs. Santa", and first appeared on television in the pilot episode of "South Park", "Cartman Gets an Anal Probe", on August 13, 1997.

South Park (season 9): Season nine of "South Park", an American animated television series created by Trey Parker and Matt Stone, began airing on March 9, 2005.  The ninth season concluded after 14 episodes on December 7, 2005.  All of the episodes in the ninth season were written and directed by Trey Parker.

The Death of Eric Cartman: "The Death of Eric Cartman" is the sixth episode in the ninth season of the American animated television series "South Park".  The 131st episode overall, it originally aired on Comedy Central in the United States on April 13, 2005.  In the episode, the other boys begin ignoring Cartman, leading to him concluding that he must be a ghost.

Let Go, Let Gov: "Let Go, Let Gov" is the first episode in the seventeenth season of the American animated television series "South Park".  The 238th episode of the series overall, it first aired on Comedy Central in the United States on September 25, 2013.  The episode's story satirizes the 2013 mass surveillance disclosures, and casts Eric Cartman in an Edward Snowden-like role, in which he infiltrates the NSA in protest of the agency's surveillance of American citizens.

Supporting paragraphs: The Death of Eric Cartman South Park (season 9)
Answer: Trey Parker and Matt Stone