# Define the function that will be called when the user submits its feedback (to be called in Gradio)
>>> def save_feedback(input_text:str, output_1: str, output_2:str, user_choice: int) -> None:
...     """
...     Append input/outputs and user feedback to a JSON Lines file using a thread lock to avoid concurrent writes from different users.
...     """
...     with scheduler.lock:
...         with feedback_file.open("a") as f: