Actor, bird, mammal (preview)

I'm back after a week off, Puzzlers. Let's get into the latest Sunday Puzzle:

This week's challenge comes from listener Theodore Regan, of Scituate, Mass. Name a famous actor — 4 letters in the first name, 7 letters in the last. You can change the first letter of the actor's first name to name a bird. And you can change the first letter of the actor's last name to name a mammal. Who's the actor?

Let's break this down. Here's what we need:

1. A: A list of actors (4+7 letters);
2. B: A list of birds (4 letters);
3. M: A list of mammals (7 letters);
4. f_swap: A function that takes a word/name and replaces the first letter with every other letter in the alphabet.

This seems pretty straightforward. I only see one potential pitfall: "actors" often includes men and women these days. I suspect I can find the three lists we need without having to scrape them together myself.

Good luck! See you later this week with my solution (I hope!).