Title: Walter (Muppet)
Content:  or Muppet", where the human version of Walter is portrayed by actor Jim Parsons. The scene is pivotal to the character's arc as it resolves Walter's internal issues with himself. The character's solo act of whistling in the telethon's finale was performed by musician Andrew Bird. At the conclusion of the film, Walter deduces that he is a Muppet, adopts whistling as his sole talent and joins the group as their newest member. A 2010 article from Entertainment Weekly described Walter by writing; Meet the newest member of the Muppet repertory company: Walter, a sweet, slightly naive twenty-something every-puppet who, in the movie, is the best friend and roommate of Jason Segel's character, Gary. 
Title: Dr. Teeth and the Electric Mayhem
Content: Performed by Steve Whitmire (1980–2016), Peter Linz (2017–present) Lips joined the Electric Mayhem for several numbers during the final season of The Muppet Show, playing the trumpet. His name refers to the fact that trumpet players use their lips to play. He has yellow hair, goatee and a permanent squint. His appearances on the Muppet Show were few and far between and when he did appear in the later episodes or movies, he rarely did anything besides play the trumpet. One of his few speaking appearances was in the Shirley Bassey episode where he sang a line of "Barnyard Boogie." He was mainly created so that Whitmire could have a character to perform in the band. His lack 
Title: The Muppet Movie
Content:  The film's music was written by Kenneth Ascher and Paul Williams. Regarding the music's composition, Williams said; "Jim Henson gave you more [creative] freedom than anybody I've ever worked with in my life. I said, 'You want to hear the songs as we're writing them?' He said, 'No. I'll hear them in the studio. I know I'm gonna love them.' You just don't get that kind of freedom on a project these days." "Movin' Right Along", "Never Before, Never Again", and "I Hope That Somethin' Better Comes Along" were shortened in the film, compared to their soundtrack versions, for continuity purposes. The latter, a duet between Rowlf and Kermit, contained references that the studio considered too mature for children, although the song appeared complete in the British theatrical and home video debut versions. In "Finale: The Magic Store", a line performed by Kermit in the film is sung by Fozzie on the soundtrack recording.
Title: List of Muppets
Content: Performed by Steve Whitmire (1980–2016)  A sly and witty brown rat from the inner city, that Whitmire describes as "a sarcastic kind of New York City character"; debuted in season four.
Title: Man or Muppet
Content:  The film's writers, Nicholas Stoller and Segel, informed McKenzie that he had to avoid alluding to the term "puppet", stating that the Muppet characters view themselves as actual people, and never as sentient puppet figures. McKenzie cited power ballads written by artists such as Eric Carmen and Harry Nilsson as inspiration for the song's tone. He also stated that the main reason for the song's inclusion in the film was to have the characters resolve the problem of coming to accept their true selves. Michael Cera and Paul Rudd were considered for the role of Walter's alter-ego. The part was eventually given to Jim Parsons, who described it as "the role of a lifetime".
Title: The Muppets
Content:  his characters beginning in 2002. At Nelson's behest, Matt Vogel gradually began performing his characters in 2008. Peter Linz joined the main cast in 2011, debuting the role of Walter in The Muppets, before inheriting four characters then-currently performed by Whitmire (Statler, Link Hogthrob, Lips, Foo-Foo), and Robin the Frog from Vogel, in 2017. Whitmire was dismissed from the cast in 2016, with Vogel cast as Kermit the Frog in 2017, and most of Whitmire's other characters assumed by the remainder of the cast. The Muppets are currently performed by a core cast of six principal puppeteers: Vogel, Jacobson, Goelz, Barretta, Rudman, and Linz, with the occasional ensemble of "additional" Muppet performers that includes Julianne Buescher, Tyler Bunch, Alice Dinnean, Bruce Lanoil, Mike Quinn and others.
Title: Steve Whitmire
Content:  role in 2017. Muppet characters original to Whitmire include Rizzo the Rat, Lips (the trumpet player from Dr. Teeth and The Electric Mayhem), Foo-Foo (Miss Piggy's dog), Wembley Fraggle and Sprocket the Dog on Fraggle Rock, and Bean Bunny, a character that originated in The Tale of the Bunny Picnic (1986). Whitmire voiced Link Hogthrob in the Muppet RaceMania and Muppets Party Cruise video games. He also performed Link for the 2011 film The Muppets. This was the first speaking appearance of the character since the death of Jim Henson, the original performer of Link. He also performed him in Muppets Most Wanted. In 2008, Whitmire took over another of Jim Henson's roles, The Muppet Newsman.
Title: The Muppets (film)
Content:  Danforth, and Michelan Sisti all performed additional roles; Bunch playing Foozie Bear, Thog and one of the hobo Muppets, Lanoil playing one of the hobo Muppets and an item of singing food, Dinnean playing Wanda and Afghan Hound, Danforth playing one of the Mutations, and Sisti playing another item of singing food. Other additional performers include Paul McGinnis, David Barclay, Greg Ballora, Kevin Carlson, Tim Blaney, Leslie Carrara-Rudolph, Kristin Charney, B.J. Guyer, Tanya Haden, Julia Gunn, Patrick Johnson, Sean Johnson, Len Levitt, James Murray, Michael Oosterom, Karen Prell, Mike Quinn, David Skelly, Andy Stone, Art Vega, Alex Villa, and Chase Woolner.
Title: List of Muppets
Content: Performed by Jim Henson (1955–1990), Steve Whitmire (1990–2016), Matt Vogel (2017–present)  A pragmatic frog who is the straight man protagonist and de facto leader of the Muppets. Created by Jim Henson and introduced in 1955 on Sam and Friends, Kermit quickly became the de facto face of the early franchise, including regularly appearing on Sesame Street, sometimes as a reporter. He starred on The Muppet Show, as the showrunner, responsible for managing the show's production, and has appeared in every Muppet-branded production since. Jim Henson was Kermit's performer from his debut until Henson's death in 1990. Steve Whitmire assumed the role and continued to perform Kermit until 2016. Matt Vogel replaced Whitmire in 2017.
Title: The Muppet Movie
Content: Jim Henson as Kermit the Frog, Rowlf the Dog, Dr. Teeth, Waldorf and The Swedish Chef ; Frank Oz as Miss Piggy, Fozzie Bear, Sam the Eagle, Animal and Marvin Suggs ; Jerry Nelson as Floyd Pepper, Crazy Harry, Robin the Frog, Lew Zealand and Camilla the Chicken ; Richard Hunt as Scooter, Statler, Janice, Sweetums and Beaker ; Dave Goelz as Gonzo the Great, Zoot, Dr. Bunsen Honeydew and Doglion ; Caroll Spinney as Big Bird  Frank Oz appears in a cameo as a biker who beats up Fozzie Bear while Steve Whitmire appears as a man in the Bogen County Fair. Also, director Tim Burton is one of the puppeteers in the final shot of the film. John Landis is also in the final shot, performing Grover. Landis and Burton were both uncredited. Many other long time members of Jim Henson's team also provided puppeteer services, including Whitmire, Kathryn Mullen, Bob Payne, Eren Ozker, Carolyn Wilcox, Olga Felgemacher, Bruce Schwartz, Michael Earl Davis, Buz Suraci, Tony Basilicato and Adam Hunt.

Question: who did the whistling in the muppet movie?
Answer: Andrew Bird.
musician Andrew Bird.