without calling PyType_Ready().

Question 1: Should the interpreter register all types with PyType_Ready()?
Many types seem to avoid it.

Question 2: To reproduce the problem, run the following code:
    def f():
        while True:
           for a in iter(range(0,1,10**20)):
              pass
    f()
And watch the memory used by the process.
How do we test this in a unittest?