Helena Bonham Carter had pie-making lessons to prepare for her new film.The actress - who plays Mrs. Lovett, a cook who uses human flesh to fill her meat pies, in musical film 'Sweeney Todd: The Demon Barber of Fleet Street' - decided to practice making pies so she would be a more convincing cook. Helena said: "I did have a few pie lessons."I love cooking although I can't say I'm a brilliant cook - but better than Mrs. Lovett. I had to learn how to make a pie. That was tricky, the whole pie making and singing at the same time."Helena also revealed she believes her character deserves to have her own TV show and line of cookery books.She is quoted by Britain's Daily Express newspaper as saying: "I wanted Mrs. Lovett to be a bit like Martha Stewart. She should have her own cooking show. It would be nice, there should definitely be a recipe book."'Sweeney Todd: The Demon Barber of Fleet Street' is directed by Helena's long-term partner Tim Burton and stars Johnny Depp as the murderous London barber.Johnny recently revealed he was terrified of singing in the film and had to take lessons from his French singer wife Vanessa Paradis.He said: "I was more frightened than anyone, except maybe Tim Burton."I've never sung before in my life, so I kept it very low key and recorded a demo in my friend's garage studio. The first person I played it for before Tim was Vanessa who gave me tips on singing, since she is a singer."