diff --git a/tests/unit/test_models/test_base_model.py b/tests/unit/test_models/test_base_model.py
index 6421e41bce..7feb273503 100644
--- a/tests/unit/test_models/test_base_model.py
+++ b/tests/unit/test_models/test_base_model.py
@@ -328,10 +328,8 @@ def test_check_well_posedness_output_variables(self):
         }
 
         # Check warning raised
-        # TODO: getting a strange bug here, related to CPython bug here:
-        #    https://bugs.python.org/issue29620
-        # with self.assertWarns(pybamm.ModelWarning):
-        model.check_well_posedness()
+        with self.assertWarns(pybamm.ModelWarning):
+            model.check_well_posedness()
 
         # Check None entries have been removed from the variables dictionary
         for key, item in model._variables.items():