Ooh,Ooh....I think I got it! 
Nicandra physalodes(shoo-fly plant)
http://www.zanthan.com/gardens/plants/nicandra.html
Looks like it to me too!!!
I see it's a native of Peru, and is also called the Apple of Peru.
It's funny because I saw something on the river, all over, growing like a weed, that looked just like it last week. I told myself, "no! Couldn't be!"
Then I read it's become a noxious weed in some areas! hahaha!!
Interesting!
Glad it's been identified, hugs, Peg
