Question: Who was a Disney writer who started out as a layout artist on 1940s cartoons including a 1943 American animated anti-Nazi propaganda short film produced by Walt Disney Productions and released in 1943 by RKO Radio Pictures ?

Context articles: Mickey's Trailer
Der Fuehrer's Face
Saludos Amigos
Clock Cleaners
Don DaGradi
Mr. Mouse Takes a Trip
Hawaiian Holiday
Symphony Hour
Education for Death
Brave Little Tailor

Mickey's Trailer is a 1938 American animated short film produced by Walt Disney Productions and released by RKO Radio Pictures.
 The cartoon stars Mickey Mouse, Donald Duck, and Goofy on a near disastrous road trip in a travel trailer.
 It was directed by Ben Sharpsteen and features the voices of Walt Disney as Mickey, Clarence Nash as Donald, and Pinto Colvig as Goofy.
 Animators include Ed Love, Louie Schmitt, Johnny Cannon, Don Patterson, Clyde Geronimi, Tom Palmer, Frenchy de Trémaudan and Cy Young.
 Pete makes a cameo in this cartoon where he is seen driving a truck during the "Runaway Trailer" sequence featuring Mickey Mouse and Donald Duck.
 This cartoon was released a year after "Snow White and the Seven Dwarfs".
Der Fuehrer's Face (originally titled Donald Duck in Nutzi Land) is a 1943 American animated anti-Nazi propaganda short film produced by Walt Disney Productions and released in 1943 by RKO Radio Pictures.
 The cartoon, which features Donald Duck in a nightmare setting working at a factory in Nazi Germany, was made in an effort to sell war bonds and is an example of American propaganda during World War II.
 The film was directed by Jack Kinney and written by Joe Grant and Dick Huemer from the original music by Oliver Wallace.
 The film is well known for Wallace's original song "Der Fuehrer's Face", which was actually released earlier by Spike Jones.
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".
Clock Cleaners is a 1937 American animated short film produced by Walt Disney Productions and released by RKO Radio Pictures.
 The cartoon follows Mickey Mouse, Donald Duck, and Goofy working as janitors in a tall clock tower.
 The film was directed by Ben Sharpsteen and features original music by Paul Smith and Oliver Wallace.
 The voice cast includes Walt Disney as Mickey, Clarence Nash as Donald, and Pinto Colvig as Goofy.
Don DaGradi (March 1, 1911 – August 4, 1991) was a Disney writer who started out as a layout artist on 1940s cartoons including "Der Fuehrer's Face" in 1943.
 He eventually moved into animated features with the film "Lady and the Tramp" in 1955.
 He also worked as a color and styling or sequence consultant on many other motion pictures for Disney.
 His greatest achievement was for his visual screenplay for "Mary Poppins" in 1964 for which he shared an Oscar nomination for Best Adapted Screenplay with Bill Walsh.
 Don DaGradi died August 4, 1991, in Friday Harbor, Washington.
 He was named a Disney Legend posthumously, only months after his death.
Mr. Mouse Takes a Trip is a 1940 American animated short film produced by Walt Disney Productions and released by RKO Radio Pictures.
 The film was directed by Clyde Geronimi and features original music by Leigh Harline and Oliver Wallace.
 The film was animated by Clyde Geronimi, Ken Muse, Ed Love, Marvin Woodward, and Ray Abrams.
 The voice cast includes Walt Disney as Mickey, Lee Millar as Pluto, and Billy Bletcher as Pete.
Hawaiian Holiday is a 1937 American animated short film produced by Walt Disney Productions and released by RKO Radio Pictures.
 The cartoon stars an ensemble cast of Mickey Mouse, Minnie Mouse, Pluto, Donald Duck, and Goofy while vacationing in Hawaii (then a territory of the United States).
 The film was directed by Ben Sharpsteen, produced by John Sutherland and features the voices of Walt Disney as Mickey, Marcellite Garner as Minnie, Clarence Nash as Donald, and Pinto Colvig as Goofy and Pluto.
 It was Disney's first film to be released by RKO, ending a five-year distributing partnership with United Artists.
Symphony Hour is a 1942 American animated short film produced by Walt Disney Productions and released by RKO Radio Pictures.
 The cartoon depicts Mickey Mouse conducting a symphony orchestra sponsored by Pete.
 The film was directed by Riley Thomson and features music adapted from the "Light Cavalry Overture" by Franz von Suppé.
 The voice cast includes Walt Disney as Mickey, Billy Bletcher as Pete, and John McLeish as a radio announcer.
Education for Death: The Making of the Nazi is an animated propaganda short film produced by Walt Disney Productions and released on January 15, 1943, by RKO Radio Pictures, directed by Clyde Geronimi and principally animated by Ward Kimball.
 The short is based on the non-fiction book of the same name by American author Gregor Ziemer.
Brave Little Tailor is a 1938 American animated short film produced by Walt Disney Productions and released by RKO Radio Pictures.
 The cartoon is an adaptation of the fairy tale "The Valiant Little Tailor" with Mickey Mouse in the title role.
 The film was directed by Bill Roberts and features original music by Albert Hay Malotte.
 The voice cast includes Walt Disney as Mickey, Marcellite Garner as Minnie, and Eddie Holden as the Giant.