Rename PyUnicode_AsString -> _PyUnicode_AsString and
PyUnicode_AsStringAndSize -> _PyUnicode_AsStringAndSize to mark
them for interpreter internal use only.

We'll have to rework these APIs or create new ones for the
purpose of accessing the UTF-8 representation of Unicode objects
for 3.1.
diff --git a/Modules/ossaudiodev.c b/Modules/ossaudiodev.c
index 8f66144..5828c3f 100644
--- a/Modules/ossaudiodev.c
+++ b/Modules/ossaudiodev.c
@@ -809,7 +809,7 @@
     PyObject * rval = NULL;
 
     if (PyUnicode_Check(nameobj))
-	name = PyUnicode_AsString(nameobj);
+	name = _PyUnicode_AsString(nameobj);
     
     if (strcmp(name, "closed") == 0) {
         rval = (self->fd == -1) ? Py_True : Py_False;