* Improve code for the empty frozenset singleton:
- Handle both frozenset() and frozenset([]).
- Do not use singleton for frozenset subclasses.
- Finalize the singleton.
- Add test cases.
* Factor-out set_update_internal() from set_update(). Simplifies the
code for several internal callers.
* Factor constant expressions out of loop in set_merge_internal().
* Minor comment touch-ups.
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index 0ac46f0..9e53564 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -420,6 +420,7 @@
PyCFunction_Fini();
PyTuple_Fini();
PyList_Fini();
+ PySet_Fini();
PyString_Fini();
PyInt_Fini();
PyFloat_Fini();