Question about PyDict_SetItemString

[lgx]

Does PyDict_SetItemString(pDict,"key",PyString_FromString("value"))
cause memory leak?

>From Google results, I find some source code write like that. But some
code write like below:

obj =  PyString_FromString("value");
PyDict_SetItemString(pDict,"key",obj);
Py_DECREF(obj);

So, which one is correct?