Question: What star of "I Love Lucy" also starred in "DuBarry Was a Lady"?
Context: I Love Lucy, a.k.a. I Love Lucy: The Movie is a 1953 American feature film spin-off of the sitcom "I Love Lucy".  Except for one test screening in Bakersfield, California, the film was never theatrically released and was shelved. Du Barry Was a Lady is a Broadway musical, with music and lyrics by Cole Porter, and the book by Herbert Fields and B.G. DeSylva.  The musical starred Bert Lahr, Ethel Merman and Betty Grable, and the song "Friendship" was one of the highlights.  The musical was made into a 1943 Technicolor film, "Du Barry Was a Lady", starring Red Skelton, Lucille Ball, and Gene Kelly. Moonlight and Pretzels is a 1933 American Pre-Code musical film directed by Karl Freund about a man who puts on a Broadway show.  The film was released by Universal Studios, and featured Mary Brian and William Frawley, best known as "Fred Mertz" on "I Love Lucy"; Freund was a cinematographer for "I Love Lucy". Lucy and Ricky Ricardo are fictional characters from the American television sitcom "I Love Lucy", portrayed respectively by Lucille Ball and Desi Arnaz.  The Ricardos also appear in "The Lucy–Desi Comedy Hour", and Lucy also appears in one episode of "The Ann Sothern Show". Richard Denning (March 27, 1914 – October 11, 1998) was an American actor best known for starring in science fiction films of the 1950s, including "Unknown Island" (1948), "Creature from the Black Lagoon" (1954), "Target Earth" (1954), "Day the World Ended" (1955), "Creature with the Atom Brain" (1955), and "The Black Scorpion" (1957).  Denning also appeared in the film "An Affair to Remember" (1957) with Cary Grant and on radio with Lucille Ball, as George and Liz Cooper, in "My Favorite Husband" (1948–1951), the forerunner of television's "I Love Lucy".  His character's name on CBS Radio's "My Favorite Husband" was changed from George Cugat to George Cooper later in 1948.  A television version of "My Favorite Husband" (1953-1955) was broadcast on CBS for two seasons during the tenure of "I Love Lucy". Enrique Alberto Ricardo IV, "Little Ricky," is a fictional character from the American television series "I Love Lucy" (1951–57, with Ricky Jr. becoming a part of the show as of his birth in 1953) and "The Lucy-Desi Comedy Hour" (1957–60).  Little Ricky was played by a number of actors, including James John Ganzer, twins Richard and Ronald Lee Simmons, twins Michael and Joseph Mayer and, most notably, Keith Thibodeaux, billed as Little Ricky.  Although the "I Love Lucy" announcer and the opening credits of "The Lucy-Desi Comedy Hour" gave his stage name as "Little Ricky", in his post-"Lucy" acting career, particularly his four-year irregular stint on "The Andy Griffith Show", he was billed as Richard Keith. Keith Thibodeaux (born December 1, 1950) is a former American child actor of television and film and musician, best known for playing Little Ricky on the television sitcom's "I Love Lucy" and "The Lucy-Desi Comedy Hour", his last name "Thibodeaux" which was Cajun French was changed by co-star Desi Arnaz, to "Keith" because his surname was more difficult to pronounce.  He is the last living regular appearing cast member from "I Love Lucy". Desiderio Alberto Arnaz y de Acha III (March 2, 1917 – December 2, 1986), better known as Desi Arnaz or Desi Arnaz, Sr., was a Cuban-born American actor, musician, and television producer.  He is best remembered for his role as Ricky Ricardo on the American television series sitcom "I Love Lucy".  He co-starred on that show with Lucille Ball, to whom he was married at the time.  He and Ball are generally credited as the inventors of the syndicated rerun, which they pioneered with the "I Love Lucy" series. Sarah Key is the author of six books in the Hollywood Hotplates series.  They are: "The Wizard of Oz Cookbook", "The Casablanca Cookbook", "The Some Like it Hot Cookbook", and the "It's a Wonderful Life Cookbook", "A Christmas Carol Cookbook", and "The I Love Lucy Cookbook".  The "I Love Lucy Cookbook" includes recipes from foods that appeared on the television show.  Key collaborated with Jennifer Newman Brazil and Vicki Wells on "The Casablanca Cookbook: Wining and Dining at Rick's", in which the recipes are not necessarily featured in the movie, but are Moroccan in origin and "connected lightheartedly to the film." Lucille Désirée Ball (August 6, 1911 – April 26, 1989) was an American actress, comedienne, model, film-studio executive, and producer.  She was best known as the star of the self-produced sitcoms "I Love Lucy", "The Lucy–Desi Comedy Hour", "The Lucy Show", "Here's Lucy", and "Life with Lucy".
Answer: Lucille Ball