diff --git a/scripts/projects.py b/scripts/projects.py
index 846305d8..8de62adb 100644
--- a/scripts/projects.py
+++ b/scripts/projects.py
@@ -858,7 +858,7 @@ class Projects(object):
         self.read_dep_graph(args.module, args.flavour, graph)
         unvisited = graph.keys()
         temp = set()
-        while len(unvisited) is not 0:
+        while len(unvisited) != 0:
             m = unvisited[0]
             self.debug('checking circular dependency of', m)
             last = self.check_circular_deps(m, args.flavour, self.flip_graph(graph), unvisited, temp, path)