Use _PyObject_CallNoArg()

Replace:
    PyObject_CallFunctionObjArgs(callable, NULL)
with:
    _PyObject_CallNoArg(callable)
diff --git a/Objects/complexobject.c b/Objects/complexobject.c
index 31e1278..0d391e5 100644
--- a/Objects/complexobject.c
+++ b/Objects/complexobject.c
@@ -273,7 +273,7 @@
 
     f = _PyObject_LookupSpecial(op, &PyId___complex__);
     if (f) {
-        PyObject *res = PyObject_CallFunctionObjArgs(f, NULL);
+        PyObject *res = _PyObject_CallNoArg(f);
         Py_DECREF(f);
         if (res != NULL && !PyComplex_Check(res)) {
             PyErr_SetString(PyExc_TypeError,