diff --git a/zerver/tests/test_realm.py b/zerver/tests/test_realm.py
index 1dbf68769e..5a25351cab 100644
--- a/zerver/tests/test_realm.py
+++ b/zerver/tests/test_realm.py
@@ -484,17 +484,20 @@ class RealmTest(ZulipTestCase):
         realm = get_realm("zulip")
         self.assertEqual(realm.email_address_visibility, Realm.EMAIL_ADDRESS_VISIBILITY_ADMINS)
 
-    def test_change_stream_creation_policy(self) -> None:
+    def _test_change_stream_creation_policy(self, stream_policy: str) -> None:
         # We need an admin user.
         self.login("iago")
-        req = dict(create_stream_policy=orjson.dumps(Realm.POLICY_ADMINS_ONLY).decode())
+        req = {stream_policy: orjson.dumps(Realm.POLICY_ADMINS_ONLY).decode()}
         result = self.client_patch("/json/realm", req)
         self.assert_json_success(result)
 
         invalid_value = 10
-        req = dict(create_stream_policy=orjson.dumps(invalid_value).decode())
+        req = {stream_policy: orjson.dumps(invalid_value).decode()}
         result = self.client_patch("/json/realm", req)
-        self.assert_json_error(result, "Invalid create_stream_policy")
+        self.assert_json_error(result, f"Invalid {stream_policy}")
+
+    def test_change_stream_creation_policy(self) -> None:
+        self._test_change_stream_creation_policy("create_stream_policy")
 
     def test_change_invite_to_stream_policy(self) -> None:
         # We need an admin user.