Does anyone else say "Have a poo?"

Does anyone else say "I'm going to have a poo/crap/shit" at all? I know "take" is the more common way to say it, but I think "have a poo" all the time to myself.

I'm wondering if it's really a thing, because I thought of a joke that will only work if people do say "have a poo."

What's the difference between a cake and a poo?

Spoiler for answer:

You can't have a cake and eat it too.

If people don't say "have a poo," I think we need to get organized and launch a psy-ops campaign to spread this idiom with an endgame of me telling the joke sometime in 2017.