Issue #18189: add test_delegator for Idle Delegator class.
Also change private dict used as a set to a set.
Issue #7136: In the Idle File menu, "New Window" is renamed "New File".
Patch by Tal Einat, Roget Serwy, and Todd Rovito.
Issue #18339: Negative ints keys in unpickler.memo dict no longer cause a
segfault inside the _pickle C extension.
Singular form just like the other error message.
Issue #17097: Make multiprocessing ignore EINTR.
Issue #18339: use with self.assertRaises() to make test case more readable
Issue #18328: Reorder ops in PyThreadState_Delete*() functions. Now the
tstate is first removed from TLS and then deallocated.
CID 1019639 (#1 of 1): Use after free (USE_AFTER_FREE)
 use_after_free: Using freed pointer tstate.