diff --git a/tools/python/xen/util/pci.py b/tools/python/xen/util/pci.py
index 70758e4e4e..b7e34da36d 100644
--- a/tools/python/xen/util/pci.py
+++ b/tools/python/xen/util/pci.py
@@ -19,6 +19,12 @@ from xen.xend import sxp
 from xen.xend.XendConstants import AUTO_PHP_SLOT
 from xen.xend.XendSXPDev import dev_dict_to_sxp
 
+# for 2.3 compatibility
+try:
+    set()
+except NameError:
+    from sets import Set as set
+
 PROC_PCI_PATH = '/proc/bus/pci/devices'
 PROC_PCI_NUM_RESOURCES = 7