Index: python-jsonschema/jsonschema/tests/_helpers.py
===================================================================
--- python-jsonschema.orig/jsonschema/tests/_helpers.py
+++ python-jsonschema/jsonschema/tests/_helpers.py
@@ -18,7 +18,7 @@ def bug(issue=None):
     return message
 
 
-def test_suite_bug(issue):
+def test_suite_bug(issue=None):
     return (
         "A known test suite bug. "
         f"See {urljoin(TEST_SUITE_ISSUES_URL, str(issue))}."