diff --git a/ixmp/tests/test_model.py b/ixmp/tests/test_model.py
index d9fd14ba2..58751f1f6 100644
--- a/ixmp/tests/test_model.py
+++ b/ixmp/tests/test_model.py
@@ -155,6 +155,8 @@ def test_error_message(self, test_data_path, test_mp):
 For details, see the terminal output above, plus:
 Listing   : {}
 Log file  : {}
-Input data: {}""".format(*paths),
+Input data: {}""".format(
+                *paths
+            ),
         ):
             s.solve(model_file=test_data_path / "_abort.gms", use_temp_dir=False)