Update async a bit

capnp/async.pyx

@@ -14,7 +14,7 @@ from cython.operator cimport dereference as deref
 cdef extern from "<utility>" namespace "std":
     async.PyPromise movePromise"std::move"(async.PyPromise)
 
-# This is a really weird function. By making it public, we'll be able to call it from asyncHelper.h
+# By making it public, we'll be able to call it from asyncHelper.h
 cdef public object wrap_kj_exception(async.Exception & exception):
     return None # TODO
 

capnp/asyncHelper.h

@@ -1,6 +1,6 @@
 #include "kj/async.h"
 #include "Python.h"
-#include <iostream>
+
 extern "C" {
    PyObject * wrap_kj_exception(kj::Exception &);
 }
@@ -8,7 +8,6 @@ extern "C" {
 PyObject * wrapPyFunc(PyObject * func, PyObject * arg) {
     PyObject * result = PyObject_CallFunctionObjArgs(func, arg, NULL);
     Py_DECREF(func);
-    Py_DECREF(arg);
     return result;
 }