diff --git a/test/test_utils.py b/test/test_utils.py
index fb7d357a8..8f4b40593 100644
--- a/test/test_utils.py
+++ b/test/test_utils.py
@@ -11,7 +11,7 @@ def test_bidi():
 
 
 def test_hexdump():
-    assert list(utils.hexdump("one\0" * 10))
+    assert list(utils.hexdump(b"one\0" * 10))
 
 
 def test_clean_bin():