1061     PyTupleObject *it_seq; /* Set to NULL when iterator is exhausted */  member
1068     Py_XDECREF(it->it_seq);  in tupleiter_dealloc()
1075     Py_VISIT(it->it_seq);  in tupleiter_traverse()
1086     seq = it->it_seq;  in tupleiter_next()
1098     it->it_seq = NULL;  in tupleiter_next()
1107     if (it->it_seq)  in tupleiter_len()
1108         len = PyTuple_GET_SIZE(it->it_seq) - it->it_index;  in tupleiter_len()
1118     if (it->it_seq)  in tupleiter_reduce()
1120                              it->it_seq, it->it_index);  in tupleiter_reduce()
1131     if (it->it_seq != NULL) {  in tupleiter_setstate()
1134         else if (index > PyTuple_GET_SIZE(it->it_seq))  in tupleiter_setstate()
1135             index = PyTuple_GET_SIZE(it->it_seq); /* exhausted iterator */  in tupleiter_setstate()
1198     it->it_seq = (PyTupleObject *)seq;  in tuple_iter()