Question: Which American actor made a cameo voiceover role as a flight attendant on the 1942 American animated movie "Saludos Amigos"?

full_context: Document 1: South of the Border with Disney: South of the Border with Disney is a 1942 Disney short documentary film. It was shot in the same occasion "Saludos Amigos" was, when Walt Disney and a group of eighteen artists, musicians and writers went to South America looking for inspirations for a movie. While "Saludos Amigos" is the result of this voyage, alternating animated shorts to the sequences from the travel that inspired them, "South of the Border with Disney" is more of a behind-the-scenes documentary showing only the travel and the genesis of cartoons not only for "Saludos Amigos" and "The Three Caballeros", but also some others used in later occasions. The most notable example is a female Armadillo used for a 1943 Pluto cartoon, "Pluto and the Armadillo". Film also includes some pencil test animation.
Document 2: Mel Stuart: Mel Stuart (born Stuart Solomon; September 2, 1928 – August 9, 2012) was an American film director and producer, who often worked with producer David L. Wolper, whose production firm he worked for 17 years, before going freelance.
Document 3: Stuart Buchanan: Stuart Buchanan (March 18, 1894 – February 4, 1974) was an American actor and deep-voice announcer, who was the casting director for the Walt Disney Company, best known for voicing Humbert the Huntsman in the 1937 Disney animated film "Snow White and the Seven Dwarfs". He also made cameo voiceover roles as a flight attendant in "Saludos Amigos" (1942) and in "Super-Speed" (1935). He also voiced Goofy in "The Mickey Mouse Theater of the Air" in 1938.
Document 4: Paul Bunyan (film): Paul Bunyan is a 1958 animated musical short film released by Walt Disney Studios It was based on the North American folk hero and lumberjack Paul Bunyan. The film was directed by Les Clark, a member of Disney's Nine Old Men of core animators. Thurl Ravenscroft starred as the voice of Paul Bunyan. Supporting animators on the project included Lee Hartman.
Document 5: Don Donald: Don Donald is a 1937 American animated short film produced by Walt Disney Productions and released by United Artists. The cartoon follows Donald Duck attempting to woo a female Mexican duck named Donna. It was directed by Ben Sharpsteen and features music by Paul J. Smith which was adapted from the Mexican folk songs "Cielito Lindo" and "Jarabe Tapatío." Clarence Nash voiced both Donald and Donna.
Document 6: Donald Duck talk: Donald Duck voice, formally called buccal speech, is an alaryngeal form of vocalization which uses the inner cheek to produce sound rather than the larynx. The speech is most closely associated with the Disney cartoon character Donald Duck whose voice was created and performed by voice actor Clarence Nash, and by Tony Anselmo after Nash's death in 1985.
Document 7: Frank Duck Brings 'Em Back Alive: Frank Duck Brings 'Em Back Alive is a 1946 animated short film produced by Walt Disney Productions and released by RKO Radio Pictures. In this installment of the "Donald & Goofy" series, Donald Duck appears as "Frank Duck", a jungle explorer determined to capture a live "wild man", played by Goofy. The film was directed by Jack Hannah and features the voices of Clarence Nash as Donald and Pinto Colvig as Goofy.
Document 8: H. Bruce Humberstone: H. Bruce "Lucky" Humberstone (November 18, 1901 – October 11, 1984) was a movie actor (as a child), a script clerk, an assistant director, working with directors such as King Vidor, Edmund Goulding and Allan Dwan and, ultimately, a director.
Document 9: Sterling Holloway: Sterling Price Holloway Jr. (January 4, 1905 – November 22, 1992) was an American actor and voice actor who appeared in over 100 films and 40 television shows. He was also a voice actor for The Walt Disney Company, well known for his distinctive tenor voice, and served as the original voice of the title character in Walt Disney's "Winnie the Pooh".
Document 10: Saludos Amigos: Saludos Amigos (Spanish for "Greetings, Friends") is a 1942 American live-action animated package film produced by Walt Disney and released by RKO Radio Pictures. It is the sixth Disney animated feature film and the first of the six package films produced by Walt Disney Productions in the 1940s. Set in Latin America, it is made up of four different segments; Donald Duck stars in two of them and Goofy stars in one. It also features the first appearance of José Carioca, the Brazilian cigar-smoking parrot. "Saludos Amigos" was popular enough that Walt Disney decided to make another film about Latin America, "The Three Caballeros", to be produced two years later. "Saludos Amigos" premiered in Rio de Janeiro on August 24, 1942. It was released in the United States on February 6, 1943. At 42 minutes, it is Disney's shortest animated feature to date. It garnered positive reviews and was theatrically reissued in 1949, when it was shown on a double bill with the first reissue of "Dumbo".
Document 11: Pinto Colvig: Vance DeBar "Pinto" Colvig (September 11, 1892 – October 3, 1967) was an American vaudeville actor, voice actor, radio actor, newspaper cartoonist, and circus performer, whose schtick was playing the clarinet off-key while mugging. Colvig was the original Bozo The Clown, and the original voice of the Disney character Goofy. In 1993, he was posthumously made a Disney Legend for his contributions to Walt Disney films, including "Snow White and the Seven Dwarfs" and "Fun and Fancy Free".
Document 12: Art Babbitt: Arthur Harold Babitsky (October 8, 1907 – March 4, 1992), better known as Art Babbitt, was an American animator, best known for his work at The Walt Disney Company. He received over 80 awards as an animation director and animator, and also developed the character of Goofy. Babbitt worked as an animator or animation director on such films as "The Three Little Pigs" (1933), "Snow White and the Seven Dwarfs" (1937), "Fantasia" (1940), and "The Incredible Mr. Limpet" (1964), among others.
Document 13: Panchito Pistoles: Panchito Pistoles is a cartoon character drawn as an anthropomorphized rooster. He appeared in the film "The Three Caballeros". Later he appeared in several Disney comics, including Don Rosa's "The Three Caballeros Ride Again" and "The Magnificent Seven (Minus 4) Caballeros". Panchito was the only one of the Three Caballeros to never appear in "Saludos Amigos", as he did not yet exist when the 1942 film was released before he first appeared in the 1944 film.
Document 14: The Three Caballeros: The Three Caballeros is a 1944 American live-action animated musical package film produced by Walt Disney and released by RKO Radio Pictures. The film premiered in Mexico City on December 21, 1944. It was released in the United States on February 3, 1945 and in the UK that March. The seventh Disney animated feature film, the film plots an adventure through parts of Latin America, combining live-action and animation. This is the second of the six package films released by Walt Disney Productions in the 1940s, following "Saludos Amigos" (1942).
Document 15: José Carioca: José "Zé" Carioca ( ; ] ] ) is a Disney cartoon character drawn as an anthropomorphic parrot from Rio de Janeiro, Brazil (thus "Carioca", a term which refers to a person born there). José was created in 1942 for the movie "Saludos Amigos" as a friend of Donald Duck, described by "Time" as "a dapper Brazilian parrot, who is as superior to Donald Duck as the Duck was to Mickey Mouse". He returned in the 1944 film "The Three Caballeros" along with Donald and a Mexican rooster named Panchito Pistoles.
ground_truth: Stuart Buchanan