I mea, *really* equal -- for now, the implementation just imports
itertools. :-)
The only other changes necessary were various unit tests that were
assuming zip() returns a real list. No "real" code made this assumption.
test_tuple.py and test_list.py. Common tests for tuple, list and UserList
are shared (in seq_tests.py and list_tests.py). Port tests to PyUnit.
(From SF patch #736962)