This 9 July 2019 video says about itself:
What’s Inside A Turtle Shell
A turtle can’t crawl out of its shell. In fact, the shell is actually part of a turtle’s skeleton, as much of our ribcage is of ours. But if you could peer inside a shell, you’d find some of the most unusual features in the animal kingdom, such as a butt — err, cloaca — that some species use to breathe underwater.