So we were at a friend's house last night and he presents this glass wine bottle with a wine glass inside. How was this made?

So we were at a friend's house last night and he presents this glass wine bottle with a wine glass inside. How was this made?

I THINK I KNOW!
Glass wa put in from the top, then once secured.... the neck was rolled?
no bottom on the bottle?
The glass bottle and glass inside are all made from the same glass. No obvious mould line between the two. There's not even a mould line around the bottle. It's as if the entire thing was blown?!
Okay, this could have been done in a couple of ways.
Rocky Yip is onto something, I think it would make more sense if they blew a cylinder, blew a hole and opened the end, picked up the wine class out of a garage. Then punty it and pull the neck? although I don't see any scars from jacks so maybe they used a mould for the shape of the bottle before they opened the bottom?
Is there a punty scar?