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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;
 }
```