Believe it or do not, I'm actually getting e-mails from folks asking what a "pantomime goose" is. In British parlance, the word "pantomime" sometimes denotes a theatrical impersonation. In other words, when I dress up in my antelope suit, I am a "pantomime antelope." The Python boys had some running gags on their program involving a "pantomime horse" and a "pantomime Princess Margaret," and our friend Kim "Howard" Johnson has played a "pantomime goose" in some of their stage presentations.
Which is as good a time as any to mention that Kim/Howard has a website full of Python facts and features. Here's the link to (what else?) The Pantomime Goose.