diff --git a/test/testfilemanip.py b/test/testfilemanip.py
index f8f8fc1..63b6c2b 100755
--- a/test/testfilemanip.py
+++ b/test/testfilemanip.py
@@ -132,7 +132,7 @@ class SHA256TransactionTest(unittest.TestCase):
         self.testcases = ["", "abc", "©", "\ufeff"]
 
     def generate_len_and_hash(self, func, data):
-        s = data.encode()
+        s = data.encode('utf-8')
         h = func()
         h.update(s)
         return "%s:%s" % (len(s), h.hexdigest())