Specifically, there are two loops, one nested inside the other, and the total number of iterations is 1 billion.
I was hoping this would test how long it takes to compile 1 billion nested loops. As in, a 2-billion-line source file where the first billion lines each open a loop and the next billion lines close them all. That would be… interesting. Pointless, but interesting.
I would expect that would break the Python interpreter. Hmm. Now you have me wanting to try it. Writing Python that writes Python is always fun.
The indentation alone would be half an exabyte. You could transform it into an equivalent representation with a billion-variable list (or numpy array) that should fit within the limits of the interpreter.