diff --git a/skimage/graph/tests/test_rag.py b/skimage/graph/tests/test_rag.py
index af325215..8179b92f 100644
--- a/skimage/graph/tests/test_rag.py
+++ b/skimage/graph/tests/test_rag.py
@@ -34,7 +34,7 @@ def test_rag_merge():
     g.merge_nodes(1, 4)
     g.merge_nodes(2, 3)
     g.merge_nodes(3, 4)
-    assert sorted(g.node[4]['labels']) == range(5)
+    assert sorted(g.node[4]['labels']) == list(range(5))
     assert g.edges() == []