diff --git a/qualibrate_composite/cli/config.py b/qualibrate_composite/cli/config.py
index bf5f8ee..feb2461 100644
--- a/qualibrate_composite/cli/config.py
+++ b/qualibrate_composite/cli/config.py
@@ -119,9 +119,9 @@ def _qualibrate_config_from_sources(
             if not_default_arg or (
                 timeline_db_mapping[arg_key] not in from_file["timeline_db"]
             ):
-                from_file["timeline_db"][timeline_db_mapping[arg_key]] = (
-                    arg_value
-                )
+                from_file["timeline_db"][
+                    timeline_db_mapping[arg_key]
+                ] = arg_value
         elif arg_key in runner_mapping.keys():
             if not_default_arg or (
                 runner_mapping[arg_key] not in from_file["runner"]