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In _PyStructSequence_InitType, it will check type is initialized.
but when we have multi subinterpreters, type may be initialized expected.
when type already been initialized, should return 0 rather than throw exception.
```c
/* PyTypeObject has already been initialized */
if (Py_REFCNT(type) != 0) {
 return 0;
}
```
```c
int
_PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc,
 unsigned long tp_flags)
{
 PyMemberDef *members;
 Py_ssize_t n_members, n_unnamed_members;
#ifdef Py_TRACE_REFS
 /* if the type object was chained, unchain it first
 before overwriting its storage */
 if (type->ob_base.ob_base._ob_next) {
 _Py_ForgetReference((PyObject *)type);
 }
#endif
 /* PyTypeObject has already been initialized */
 if (Py_REFCNT(type) != 0) {
 PyErr_BadInternalCall();
 return -1;
 }
```

> In _PyStructSequence_InitType, it will check type is initialized.
 It's a internal C API :)
> when type already been initialized, should return 0 rather than throw exception.
 The another solution is to check the type status before calling _PyStructSequence_InitType().

Include/internal/pycore_structseq.h:
 10 
 11 
 12: PyAPI_FUNC(int) _PyStructSequence_InitType(
 13 PyTypeObject *type,
 14 PyStructSequence_Desc *desc,
Modules/_cursesmodule.c:
 4794 /* ncurses_version */
 4795 if (NcursesVersionType.tp_name == NULL) {
 4796: if (_PyStructSequence_InitType(&NcursesVersionType,
 4797 &ncurses_version_desc,
 4798 Py_TPFLAGS_DISALLOW_INSTANTIATION) < 0) {
Objects/structseq.c:
 463 
 464 int
 465: _PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc,
 466 unsigned long tp_flags)
 467 {
 ...
 527 PyStructSequence_InitType2(PyTypeObject *type, PyStructSequence_Desc *desc)
 528 {
 529: return _PyStructSequence_InitType(type, desc, 0);
 530 }
 531 
Python/sysmodule.c:
 2813 /* version_info */
 2814 if (VersionInfoType.tp_name == NULL) {
 2815: if (_PyStructSequence_InitType(&VersionInfoType,
 2816 &version_info_desc,
 2817 Py_TPFLAGS_DISALLOW_INSTANTIATION) < 0) {
 ....
 2827 // sys.flags: updated in-place later by _PySys_UpdateConfig()
 2828 if (FlagsType.tp_name == 0) {
 2829: if (_PyStructSequence_InitType(&FlagsType, &flags_desc,
 2830 Py_TPFLAGS_DISALLOW_INSTANTIATION) < 0) {
 2831 goto type_init_failed;
 ....
 2837 /* getwindowsversion */
 2838 if (WindowsVersionType.tp_name == 0) {
 2839: if (_PyStructSequence_InitType(&WindowsVersionType,
 2840 &windows_version_desc,
 2841 Py_TPFLAGS_DISALLOW_INSTANTIATION) < 0) {

OK,thanks. If it's just only interal calling, I don't think throwing a exception would break anything. As your pasted code shows, the modules have judeged the tp_name is inited or not.