diff --git a/Snakefile b/Snakefile
index a59025f9..0bb1b665 100644
--- a/Snakefile
+++ b/Snakefile
@@ -30,7 +30,6 @@ if run["name"]:
 else:
     RDIR = ""
 
-# for possibly shared resources
 logs = path_provider("logs/", RDIR, run["shared_resources"])
 benchmarks = path_provider("benchmarks/", RDIR, run["shared_resources"])
 resources = path_provider("resources/", RDIR, run["shared_resources"])
@@ -38,14 +37,6 @@ resources = path_provider("resources/", RDIR, run["shared_resources"])
 CDIR = "" if run["shared_cutouts"] else RDIR
 RESULTS = "results/" + RDIR
 
-# TODO: this needs to be aligned with new scenario management
-# if not (shared_resources := run.get("shared_resources")):
-#     RESOURCES = "resources/" + RDIR
-# elif isinstance(shared_resources, str):
-#     RESOURCES = "resources/" + shared_resources + "/"
-# else:
-#     RESOURCES = "resources/"
-
 
 localrules:
     purge,
diff --git a/scripts/_helpers.py b/scripts/_helpers.py
index f1c659ec..06e68325 100644
--- a/scripts/_helpers.py
+++ b/scripts/_helpers.py
@@ -321,7 +321,7 @@ def progress_retrieve(url, file, disable=False):
 def mock_snakemake(
     rulename,
     root_dir=None,
-    configfiles=[],
+    configfiles=None,
     submodule_dir="workflow/submodules/pypsa-eur",
     **wildcards,
 ):
@@ -375,7 +375,9 @@ def mock_snakemake(
             if os.path.exists(p):
                 snakefile = p
                 break
-        if isinstance(configfiles, str):
+        if configfiles is None:
+            configfiles = []
+        elif isinstance(configfiles, str):
             configfiles = [configfiles]
 
         workflow = sm.Workflow(
@@ -397,7 +399,7 @@ def mock_snakemake(
 
         def make_accessable(*ios):
             for io in ios:
-                for i in range(len(io)):
+                for i, _ in enumerate(io):
                     io[i] = os.path.abspath(io[i])
 
         make_accessable(job.input, job.output, job.log)