"The Woody Woodpecker Polka" from 1951 is Oswald The Lucky Rabbit's last appearance.
Like most cartoon characters of the era, Woody appears here in drag, quite convincingly. And he breaks the fourth wall silently, to assure the audience it's still really him.
The tune of the Woody Woodpecker Polka is based on the popular dance number, The Pennsylvania Polka.
The humor in this short was decidedly adult in some cases, though nothing that would have attracted the censors. There were also plenty of slapstick sight and sound gags to appeal to younger viewers. TV broadcast of the shorts would not begin until 1957, so this was likely designed to be shown as part of a cinema program.