title: lost on Py_DECREF/INCREF when handling PyList_Append in Python C extension
body: <p>I am lost on Py_DECREF/INCREF when handling PyList_Append. Can anybody have comments on the following codes?</p>
  
  <pre><code>PyObject * bugmaybe(PyObject *self, PyObject *args)
  {
     PyObject * trio=PyList_New(0);
     PyObject * trio_tmp;
     PyObject * otmp = PyFloat_FromDouble(1.2);
     PyList_Append(trio_tmp,otmp);
     //Py_DECREF(otmp);
     otmp = PyFloat_FromDouble(2.3);
     PyList_Append(trio_tmp,otmp);
     //Py_DECREF(otmp);
     PyList_Append(trio,trio_tmp);
     Py_INCREF(trio_tmp);
  }
  </code></pre>