Improve code readability

utils.py

@@ -39,8 +39,8 @@ def initialize_run_directory(model: OpenAI | Llama2):
     response, usage = model(None, run_name_prompt, chat=True)
     model.usage -= usage
     run_name_match = re.search(r"^\w+$", response, re.MULTILINE)
-    existing_dirs = os.listdir(RUNS_DIR)
-    if run_name_match is None or run_name_match.group(0) in existing_dirs:
+    existing_run_names = os.listdir(RUNS_DIR)
+    if run_name_match is None or run_name_match.group(0) in existing_run_names:
         run_name = uuid4().hex
     else:
         run_name = run_name_match.group(0)