diff --git a/benchexec/containerexecutor.py b/benchexec/containerexecutor.py
index dbc319c2d..237291207 100644
--- a/benchexec/containerexecutor.py
+++ b/benchexec/containerexecutor.py
@@ -346,12 +346,16 @@ def __init__(
         self._uid = (
             uid
             if uid is not None
-            else container.CONTAINER_UID if container_system_config else os.getuid()
+            else container.CONTAINER_UID
+            if container_system_config
+            else os.getuid()
         )
         self._gid = (
             gid
             if gid is not None
-            else container.CONTAINER_GID if container_system_config else os.getgid()
+            else container.CONTAINER_GID
+            if container_system_config
+            else os.getgid()
         )
         self._allow_network = network_access
         self._env_override = {}
diff --git a/benchexec/test_runexecutor.py b/benchexec/test_runexecutor.py
index 5f699c44b..cf7dd54d5 100644
--- a/benchexec/test_runexecutor.py
+++ b/benchexec/test_runexecutor.py
@@ -1097,6 +1097,7 @@ def test_parent_fns(self):
             self.skipTest("missing /bin/sh")
         parent_setup_ran = False
         parent_cleanup_ran = False
+
         def parent_setup_fn(*, grandchild_pid, child_pid, **kwargs):
             # I don't want to require psutil just for this
             # I'll just read the procfs
@@ -1112,6 +1113,7 @@ def parent_cleanup_fn(parent_setup, exit_code, path):
             assert parent_setup == 12345
             nonlocal parent_cleanup_ran
             parent_cleanup_ran = True
+
         self.execute_run(
             "/bin/sh",
             "-c",