Question: What U Workin' With was a song from the film based on the dolls created by whom?

Context paragraphs:
Flavas: Flavas is an American line of fashion dolls created by Mattel in 2003.  They are multi-ethnic and have an urban, hip hop style with "bling-bling" jewellery and stick-on tattoos, described as "ghetto-fabulous" by "Newsweek".  They were designed to appeal to tweens (8- to 12-year-olds) and compete with the widely successful Bratz dolls.  They were marketed as "reality-based" and "authentic" and have more points of articulation than traditional fashion dolls for more expressive posing.  Flavas were criticized for being stereotypical, bad role models, and a misrepresentation of hip hop culture.  Their multiculturalism was described as positive, and British analysts expected their "risqué nature" to translate to high sales.  But following sales that were described as "disastrous" they were discontinued within a year.

MVP Sports Stars: MVP Sports Stars were plush pillow dolls created by Ace Novelty Company released around 1991 and 1992 The sport for which they played was given a name (ie 'Tackling Dummies' for Football).

My Scene: My Scene was an American series of fashion dolls created by Mattel in 2002.  Mattel's Barbie character is one of the dolls in the My Scene line, and the My Scene dolls have slim bodies similar to earlier Barbie dolls, but with larger heads. " The New York Times" described their features as "exaggerated lips and bulging, makeup-caked eyes."  My Scene were designed to appeal to the tween market and compete with the Bratz dolls from MGA Entertainment.  The series originally consisted of three female characters, but was expanded to eventually include ten different dolls.

What U Workin' With?: "What U Workin' With?"  is a song recorded by American singers Gwen Stefani and Justin Timberlake for the official soundtrack to the 2016 film "Trolls".  Timberlake co-wrote and co-produced the track with Max Martin and Ilya Salmanzadeh with additional writing from Savan Kotecha and Peter Svensson.  The song was first announced on August 22, 2016, with Stefani's appearance being a secret.  An urban and dance song, the lyrics talk about having a good time and standing out amongst a crowd.

Teen Trends: Teen Trends was a line of dolls created by Mattel.  They featured only four dolls and were released in 2005.  They have most likely been discontinued.  Nothing new has been released since 2007.  It is unknown if they will ever release anything new again, but during the holiday shopping season of 2007 super sized Kianna dolls were being sold at Costco.  That is the most recent thing to be released in Teen Trends as of 2016.

Cabbage Patch Kids: Cabbage Patch Kids are a line of soft sculptured dolls created by Xavier Roberts and registered in the United States copyright office in 1978.

It's All About to Change: It's All About To Change is the second studio album by American country singer Travis Tritt, released on Warner Bros.  Records in 1991.  The tracks "The Whiskey Ain't Workin'", "Nothing Short of Dying", "Anymore", and "Here's a Quarter (Call Someone Who Cares)" were released as singles; "Bible Belt" also charted from unsolicited airplay.  "Anymore" was the second single of Tritt's career to reach Number One on the Hot Country Songs charts.  Overall, this is Tritt's highest-certified album; with sales of over three million copies in the U.S., it has been certified 3× Platinum by the RIAA.  He recorded the song "Bible Belt" for "My Cousin Vinny" in collaboration with the band Little Feat, and this placement gained him some exposure.

Trolls (film): Trolls is a 2016 American 3D computer-animated musical comedy film based on the Troll dolls created by Thomas Dam.  The film was directed by Mike Mitchell and co-directed by Walt Dohrn, written by Jonathan Aibel and Glenn Berger and based on a story by Erica Rivinoja.  The film features the voices of Anna Kendrick, Justin Timberlake, Zooey Deschanel, Russell Brand, James Corden and Gwen Stefani.  The film revolves around two trolls on a quest to save their village from destruction by the Bergens, creatures who eat trolls.

Diva Starz: Diva Starz was a series of fashion dolls created and released by Mattel during the Christmas shopping season of 2000.  They are similar in design to the MGA Entertainment Bratz dolls released in 2001, and the Flavas dolls released by Mattel in 2003.  Four dolls (Alexa, Tia, Summer, and Nikki) were offered in the original debut.  The line was discontinued in 2004.

Krypt Kiddies: Krypt Kiddies are a line of horror dolls created by Uhl House that appeared in Spencer's Gifts in 2003.

Supporting paragraphs: What U Workin' With? Trolls (film)
Answer: Thomas Dam