> A builtin frozendict type "compatible" with the PyDict C API is very > convinient for pysandbox because using this type for core features > like builtins requires very few modification. For example, use > frozendict for __builtins__ only requires to modify 3 lines in > frameobject.c. See the frozendict_builtins.patch attached to the issue #14162. Last version: http://bugs.python.org/file24690/frozendict_builtins.patch Victor