Query: Which film project did Madonna leave because of differences with the director?
Context: The 1998 edition of Guinness Book of World Records stated: "No female artist has sold more records than Madonna around the world". In 1999 Madonna signed to play a violin teacher in the film Music of the Heart but left the project, citing "creative differences" with director Wes Craven. She recorded the single "Beautiful Stranger" for the 1999 film Austin Powers: The Spy Who Shagged Me.