Knock knock. Who's there? Pecan.

Pecan who? Pecan-der this: it's a nut-terly punishing joke, but I shelled out for the delivery!

Knock knock. Who's there? Silence.

Knock knock. Who's there? An incomplete thought.

An incomplete thought who? An incomplete thought about... what was I saying?

Knock knock. Who's there? Pane

Pane who? I'm having a window of opportunity to let you in.