Isadore "Izzy" Klein (1897-1986) was an American author-screenwriter and animator. He began his career as an author and then an animator at Disney Studios in 1936. From 1942, he worked as an author-animator for the Terrytoons studio. He stopped working as an animator in favor of scriptwriting. In the early 1960s, Klein resumed animation while remaining a screenwriter. He retired in 1969.

[biography, translated and adapted, from French Wikipedia]