This reverts r63675 based on the discussion in this thread:

 http://mail.python.org/pipermail/python-dev/2008-June/079988.html

Python 2.6 should stick with PyString_* in its codebase.  The PyBytes_* names
in the spirit of 3.0 are available via a #define only.  See the email thread.
diff --git a/Objects/cellobject.c b/Objects/cellobject.c
index 16bb150..4e0bcf8 100644
--- a/Objects/cellobject.c
+++ b/Objects/cellobject.c
@@ -73,9 +73,9 @@
 cell_repr(PyCellObject *op)
 {
 	if (op->ob_ref == NULL)
-		return PyBytes_FromFormat("<cell at %p: empty>", op);
+		return PyString_FromFormat("<cell at %p: empty>", op);
 
-	return PyBytes_FromFormat("<cell at %p: %.80s object at %p>",
+	return PyString_FromFormat("<cell at %p: %.80s object at %p>",
 				   op, op->ob_ref->ob_type->tp_name,
 				   op->ob_ref);
 }