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/boolobject.c b/Objects/boolobject.c
index 93affd1..fd73d28 100644
--- a/Objects/boolobject.c
+++ b/Objects/boolobject.c
@@ -25,10 +25,10 @@
 
 	if (self->ob_ival)
 		s = true_str ? true_str :
-			(true_str = PyBytes_InternFromString("True"));
+			(true_str = PyString_InternFromString("True"));
 	else
 		s = false_str ? false_str :
-			(false_str = PyBytes_InternFromString("False"));
+			(false_str = PyString_InternFromString("False"));
 	Py_XINCREF(s);
 	return s;
 }