When was the song supercalifragilisticexpialidocious written?

The song "Supercalifragilisticexpialidocious" was written by Richard M. Sherman and Robert B. Sherman for the 1964 Disney film "Mary Poppins." It was first performed by the characters Mary Poppins and Bert, played by Julie Andrews and Dick Van Dyke, respectively. The song has since become iconic, known for its whimsical lyrics and catchy melody.