The Wizard of Osbourne is a parody bit based off The Wizard of Oz.
The Wizard of Osbourne was recorded for a British comedy show Christmas special called " A Bear's Christmas Tail" which is based off a British comdey show called "Bo Selecta" which is a celebrity rubber-face comedy on Channel 4. They would have many celebrities on there and they would look nothing like them. In the special they had Craig David as The Chinman (Tin Woodman) Mel B as the Cowardly Lioness (Cowardly Lion) Jack Osbourne as the Scarecrow and Michael Jackson as Dorotay (Dorothy). All the rubber-faced celebrities are portrayed by Leigh Francis
Once one of the character's of the show turns the televison channel, it goes to the The Wizard of Osbourne which to him is the original film. In the clip Dorotay (Michael Jackson) walking with the Chinman (Craig David) and the Cowardly Lioness (Mel B), the latter says something that annoys the Chinman so he sets off on his own leaving her and Dorotay behind. So Dorotay askes a Scarecrow (Jack Osbourne) where to go to get to the Osbournes. He greets him (Shamone Scarecrow) and he greets back (Shamone Michael). But he tells him to call him Dorotay like this movie. So this proves it is a possible parody movie.