(Film critic Leonard maltin delivers the clue.)"Three Little Pigs", a Disney Silly Symphony of 1933, introduced this song that became an anti-Depression anthem
According to 
Leonard Maltin on the Walt Disney Treasures: Silly Symphonies DVD, this was 
an early... [DOC] [TLE] Walt Disney Treasures: Silly Symphonies  Animated Views [PAR] Jul 19, 2002 ... Film historian and Disney aficionado, Leonard Maltin provides an ...