973     PyTupleObject *it_seq; /* Set to NULL when iterator is exhausted */  member
980     Py_XDECREF(it->it_seq);  in tupleiter_dealloc()
987     Py_VISIT(it->it_seq);  in tupleiter_traverse()
998     seq = it->it_seq;  in tupleiter_next()
1010     it->it_seq = NULL;  in tupleiter_next()
1019     if (it->it_seq)  in tupleiter_len()
1020         len = PyTuple_GET_SIZE(it->it_seq) - it->it_index;  in tupleiter_len()
1030     if (it->it_seq)  in tupleiter_reduce()
1032                              it->it_seq, it->it_index);  in tupleiter_reduce()
1043     if (it->it_seq != NULL) {  in tupleiter_setstate()
1046         else if (index > PyTuple_GET_SIZE(it->it_seq))  in tupleiter_setstate()
1047             index = PyTuple_GET_SIZE(it->it_seq); /* exhausted iterator */  in tupleiter_setstate()
1110     it->it_seq = (PyTupleObject *)seq;  in tuple_iter()