diff --git a/tests/utils.py b/tests/utils.py
index <HASH>..<HASH> 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -1,5 +1,7 @@
 from contextlib import contextmanager
+import random
 import shutil
+import string
 from tempfile import mkdtemp
 
 
@@ -10,3 +12,7 @@ def temp_dir():
         yield dirname
     finally:
         shutil.rmtree(dirname)
+
+
+def get_random_hex_string(size=64):
+    return ''.join(random.choice(string.hexdigits) for n in range(size))
Add helper to create hex strings like sha<I>.