Tested and working simple function to join MP3 audio files one after another from given file path's list in Python

 import os

    import subprocess

    def join_mp3s(input_paths, output_path):

        if not input_paths:

            raise ValueError("Input paths cannot be empty.")

        if not output_path:

            raise ValueError("Output path cannot be missing.")

        # Create a temporary file list using a unique identifier

        temp_list_path = f"{output_path}.concat"

        with open(temp_list_path, "w") as f:

            for path in input_paths:

                f.write(f"file '{path}'\n")

        # Construct the ffmpeg command

        command = ["ffmpeg", "-f", "concat", "-safe", "0",

                "-i", temp_list_path, "-c", "copy", output_path, "-y"]

        # Execute ffmpeg and handle potential errors

        try:

            subprocess.run(command, check=True, stderr=subprocess.STDOUT)  # Combine error streams

        except subprocess.CalledProcessError as e:

            raise RuntimeError(f"Failed to join MP3s: {e.output.decode()}")

        finally:

            os.remove(temp_list_path)  # Always clean up the temporary file