bpo-37483: add _PyObject_CallOneArg() function (#14558)

diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index 15cbe5c..689e929 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -1501,7 +1501,7 @@
         goto parse_error;
     result = PyFloat_FromDouble(negate ? -x : x);
     if (type != &PyFloat_Type && result != NULL) {
-        Py_SETREF(result, PyObject_CallFunctionObjArgs((PyObject *)type, result, NULL));
+        Py_SETREF(result, _PyObject_CallOneArg((PyObject *)type, result));
     }
     return result;