diff --git a/python/sdist/amici/de_export.py b/python/sdist/amici/de_export.py
index d82618fb35..b2a56d20c1 100644
--- a/python/sdist/amici/de_export.py
+++ b/python/sdist/amici/de_export.py
@@ -2227,7 +2227,9 @@ def _compute_equation(self, name: str) -> None:
                         )
 
                     # finish chain rule for the state variables
-                    tmp_eq += smart_multiply(self.eq("ddeltaxdx")[ie], tmp_dxdp)
+                    tmp_eq += smart_multiply(
+                        self.eq("ddeltaxdx")[ie], tmp_dxdp
+                    )
                 else:
                     tmp_eq = smart_multiply(
                         self.sym("xdot") - self.sym("xdot_old"),
diff --git a/python/tests/util.py b/python/tests/util.py
index 5b214ad795..59d16fc112 100644
--- a/python/tests/util.py
+++ b/python/tests/util.py
@@ -161,8 +161,12 @@ def check_trajectories_with_forward_sensitivities(
     solver.setAbsoluteToleranceFSA(1e-15)
     solver.setRelativeToleranceFSA(1e-13)
     rdata = runAmiciSimulation(amici_model, solver=solver)
-    _check_close(rdata["x"], result_expected_x, field="x", rtol=1e-10, atol=1e-12)
-    _check_close(rdata["sx"], result_expected_sx, field="sx", rtol=1e-7, atol=1e-9)
+    _check_close(
+        rdata["x"], result_expected_x, field="x", rtol=1e-10, atol=1e-12
+    )
+    _check_close(
+        rdata["sx"], result_expected_sx, field="sx", rtol=1e-7, atol=1e-9
+    )
 
 
 def check_trajectories_with_adjoint_sensitivities(amici_model: AmiciModel):