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/genobject.c b/Objects/genobject.c
index b1c51a8..d2ef508 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -285,10 +285,10 @@
 gen_repr(PyGenObject *gen)
 {
 	char *code_name;
-	code_name = PyBytes_AsString(((PyCodeObject *)gen->gi_code)->co_name);
+	code_name = PyString_AsString(((PyCodeObject *)gen->gi_code)->co_name);
 	if (code_name == NULL)
 		return NULL;
-	return PyBytes_FromFormat("<generator object %.200s at %p>",
+	return PyString_FromFormat("<generator object %.200s at %p>",
 				   code_name, gen);
 }