Knock knock. Who's there? Wu

Wu who? Wu don't know, I'm having an identity crisis

Knock knock. Who's there? Egg

Egg who? Egg-cuse me, I'm cracking under the pressure to make a good pun.

Knock knock. Who's there? Vaughn.

Vaughn who? Vaughn voyage! Hope your journey's ship-shape and full of bon-bons!

Knock knock. Who's there? Continue.

Continue who? Continue the joke. That's the whole thing. No pun.