diff --git a/python/tests/test_dynamics.py b/python/tests/test_dynamics.py
index 736356e7c..26edb7bdc 100644
--- a/python/tests/test_dynamics.py
+++ b/python/tests/test_dynamics.py
@@ -138,11 +138,12 @@ def assert_action_set(action_set):
 
     @staticmethod
     def policy(action_set):
-        return {a: 0.0 for a in action_set}
+        # Mixed numpy array and list
+        return (action_set, [0.0] * len(action_set))
 
     @staticmethod
     def bad_policy(action_set):
-        return {1 << 31: 0.0}
+        return ([1 << 31], [0.0])
 
     def setup_method(self, method):
         self.dynamics = ecole.dynamics.PrimalSearchDynamics()
diff --git a/python/tests/test_environment.py b/python/tests/test_environment.py
index 99797f3b0..37c3cabed 100644
--- a/python/tests/test_environment.py
+++ b/python/tests/test_environment.py
@@ -21,7 +21,7 @@ def test_reset(model):
     env = MockEnvironment()
     _, _, _, _, _ = env.reset(model)
     assert model is not env.model  # Model is copied
-    assert not env.model.is_solved()
+    assert not env.model.is_solved
 
     env.dynamics.reset_dynamics.assert_called_with(env.model)
     env.dynamics.set_dynamics_random_state.assert_called()