diff --git a/aider/main.py b/aider/main.py
index 8a1c7cac1..0a5f029e7 100644
--- a/aider/main.py
+++ b/aider/main.py
@@ -541,13 +541,13 @@ def main(argv=None, input=None, output=None, force_git_root=None, return_coder=F
     all_files = args.files + (args.file or [])
     fnames = [str(Path(fn).resolve()) for fn in all_files]
     read_only_fnames = []
-    for fn in (args.read or []):
+    for fn in args.read or []:
         path = Path(fn).resolve()
         if path.is_dir():
-            read_only_fnames.extend(str(f) for f in path.rglob('*') if f.is_file())
+            read_only_fnames.extend(str(f) for f in path.rglob("*") if f.is_file())
         else:
             read_only_fnames.append(str(path))
-    #ai expand any of the read_only_fnames which are dirs to be all the files under them!
+    # ai expand any of the read_only_fnames which are dirs to be all the files under them!
     if len(all_files) > 1:
         good = True
         for fname in all_files: